Handover method, base station, and terminal device

ABSTRACT

The present patent application discloses a handover method, a base station, and a terminal device. The handover method includes: sending, by a source base station, a handover request to a target base station, where the handover request includes information about a first service of a terminal device; receiving, by the source base station, a handover response sent by the target base station, where if the first service is supported by the target base station, the handover response includes information about a handover instruction for the first service, and the handover instruction is used to instruct the terminal device to hand over the first service from the source base station to the target base station; and sending, by the source base station, a handover response to the terminal device.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Application No.PCT/CN2016/109519, filed on Dec. 12, 2016, which claims priority toChinese Patent Application No. 201610029737.5, filed on Jan. 16, 2016.The disclosures of the aforementioned applications are herebyincorporated by reference in their entireties.

TECHNICAL FIELD

The present patent application relates to the communications field, andmore specifically, to a handover method, a base station, and a terminaldevice.

BACKGROUND

A future wireless communications network needs to satisfy diversifiedservice requirements such as high-definition multi-party videocommunication, ultra-low latency Internet of Things (Internet of Things,IoT) communication, and massive machine to machine communication(Massive Machine to Machine, Massive M2M) services. These services haveimmensely varied performance requirements, and a variation range ofnetwork requirements is huge. A network slicing architecture is proposedin the industry for diversified service requirements. How to ensuremobility of a terminal device in the network slicing architecture is aproblem to be specially considered.

SUMMARY

The present patent application provides a handover method, a basestation, and a terminal device, to adapt to a network slicingarchitecture.

According to a first aspect, the present patent application provides ahandover method, including: sending, by a source base station, ahandover request to a target base station, where the handover requestincludes information about a first service of a terminal device;receiving, by the source base station, a handover response sent by thetarget base station, where if the first service is supported by thetarget base station, the handover response includes information about ahandover instruction for the first service, and the handover instructionis used to instruct the terminal device to hand over the first servicefrom the source base station to the target base station; and sending, bythe source base station, a handover response to the terminal device.

An existing handover request does not contain service type information.When the target base station has a resource, even if the target basestation cannot provide services of some service types, the target basestation should admit to server the user during admission control.However, after handover, the target base station cannot provide aservice of a corresponding type. As a result, service interruptionoccurs. In the present patent application, a handover request containsinformation about a service, and the target base station also considersa service type when sending a handover response. The target base stationcan accurately determine whether the target base station needs to accepthandover. A current service of a user is allowed admitted to the targetbase station, only when the target base station can support the service.In this way, a service interruption probability of the terminal deviceis reduced. A service interruption problem caused by mobility of theterminal device can be resolved to some extent.

With reference to the first aspect, in a first possible implementationof the first aspect, the handover request further includes informationabout a second service of the terminal device; and if the second serviceis not supported by the target base station, the handover responsefurther includes information about an air interface resource of thesecond service, the air interface resource is determined by the targetbase station and on which interference coordination is performed, andthe air interface resource is used by the source base station and theterminal device to transmit the second service.

Because of mobility, a terminal device may move from a source basestation supporting all service types of the terminal device to a targetbase station that does not support all the service types of the terminaldevice. In a possible processing manner, a service of a service typethat the target base station does not support is interrupted for theterminal device. However, in the present patent application, a servicethat the target base station does not support still resides in thesource base station.

The terminal device and the source base station specifically performservice transmission on some air interface resources. The target basestation performs interference coordination on the air interfaceresources. In this way, the source base station is subject to lessinterference, and a service interruption problem is avoided to someextent, so that an interruption probability caused by the mobility ofthe terminal device is reduced.

With reference to the first possible implementation of the first aspect,in a second possible implementation of the first aspect, the handoverrequest further includes quality of service information of the secondservice of the terminal device, and the air interface resource isdetermined by the target base station based on the quality of serviceinformation.

If the handover request contains the QoS information of the secondservice of the terminal device, the target base station calculates,based on the QoS information, a quantity of air interface resourcesneeded to satisfy a QoS requirement of the terminal device, and thenchooses corresponding air interface resources. In this way, airinterface resources can be dynamically determined, and utilization ofthe air interface resources is high.

With reference to any one of the first aspect, or the first and secondpossible implementations of the first aspect, in a third possibleimplementation of the first aspect, the method further includes:obtaining, by the source base station, information about supportedservice of the target base station; and the sending, by a source basestation, a handover request to a target base station includes: if thetarget base station supports the first service, sending, by the sourcebase station, the handover request to the target base station.

Optionally, the source base station considers a service type. The sourcebase station sends the handover request to the target base station onlywhen the target base station supports at least some service types of theterminal device. The source base station no longer sends the handoverrequest when the target base station supports none of services of thesource base station, so that inter-system signaling interaction isreduced.

With reference to the third possible implementation of the first aspect,in a fourth possible implementation of the first aspect, the obtaining,by the source base station, information about supported service of thetarget base station includes: receiving, by the source base station, ameasurement report sent by the terminal device, where the measurementreport includes the information about the at least one supported serviceof the target base station. The measurement report contains theinformation about the at least one supported service of the target basestation, and only one information element needs to be added to existingsignaling. In this way, processing is simple, and overheads are low.With reference to the fourth possible implementation of the firstaspect, in a fifth possible implementation of the first aspect, theobtaining, by the source base station, information about supportedservice of the target base station includes: receiving, by the sourcebase station, the information that is sent by a controller or the targetbase station and that is about the at least one supported service of thetarget base station. In this way, air interface resources can be saved.

With reference to any one of the first aspect, or the first to fifthpossible implementations of the first aspect, in a sixth possibleimplementation of the first aspect, the sending, by a source basestation, a handover request to a target base station includes: sending,by the source base station, the handover request to the target basestation by using the controller; and the receiving, by the source basestation, a handover response sent by the target base station includes:receiving, by the source base station by using the controller, thehandover response sent by the target base station. If there is nointerface between the base stations or the handover request fails to bedirectly sent between the base stations, the controller may alsocomplete handover.

With reference to any one of the first aspect, or the first to fifthpossible implementations of the first aspect, in a seventh possibleimplementation of the first aspect, the sending, by a source basestation, a handover request to a target base station includes: sending,by the source base station, the handover request to the target basestation by using a source gateway and a target gateway; and thereceiving, by the source base station, a handover response sent by thetarget base station includes: receiving, by the source base station byusing the source gateway and the target gateway, the handover responsesent by the target base station. When the source base station and thetarget base station respectively belong to two different gateways,handover may still be successfully completed.

According to a second aspect, the present patent application provides ahandover method, including: receiving, by a target base station, ahandover request sent by a source base station, where the handoverrequest includes information about a first service of a terminal device;sending, by the target base station a handover response to the sourcebase station, where if the target base station supports the firstservice, the handover response includes information about a handoverinstruction for the first service, and the handover instruction is usedto instruct the terminal device to hand over the first service to thetarget base station.

With reference to any one of the second aspect, or the foregoingpossible implementations of the second aspect, in a third possibleimplementation of the second aspect, the target base station sends apath switch request to a gateway, where the path switch request includesthe information about the first service; and the target base stationreceives a path switch request acknowledgement sent by the gateway.

According to a third aspect, the present patent application provides ahandover method, including: sending, by a terminal device, a measurementreport to a source base station; and receiving, by the terminal device,a handover response, where if a first service of the terminal device issupported by a target base station, the handover response includesinformation about a handover instruction for the first service, and thehandover instruction is used to instruct the terminal device to handover the first service to the target base station.

With reference to the third aspect, in a first possible implementationof the third aspect, if a second service of the terminal device is notsupported by the target base station, the handover response furtherincludes information about an air interface resource of the secondservice, the air interface resource is determined by the target basestation and on which interference coordination is performed, and the airinterface resource is used by the terminal device and the source basestation to transmit the second service.

With reference to the first possible implementation of the third aspect,in a second possible implementation of the third aspect, the measurementreport includes information about supported service of the target basestation.

According to a fourth aspect, the present patent application provides ahandover method, including: receiving, by a gateway, a path switchrequest sent by a target base station, where the path switch requestincludes information about a first service of a terminal device; andsending, by the gateway, a path switch request acknowledgement to thetarget base station. In this way, the gateway can clearly know whichservices are switched to the target base station, and the gatewaydirectly sends downlink data of the services to the target base station,thereby ensuring normal running of a system.

According to a fifth aspect, the present patent application provides ahandover method, including: receiving, by a source gateway, a handoverrequest sent by a source base station, where the handover requestincludes information about a first service of a terminal device;sending, by the source gateway, the handover request to a targetgateway; receiving, by the source gateway, a handover response sent bythe target gateway, where if the first service is supported by a targetbase station, the handover response includes information about ahandover instruction for the first service, and the handover instructionis used to instruct the terminal device to hand over the first serviceto the target base station; and sending, by the source gateway, thehandover response to the source base station.

According to a sixth aspect, the present patent application provides ahandover method, including: receiving, by a target gateway, a handoverrequest sent by a source gateway, where the handover request includesinformation about a first service of a terminal device; sending, by thetarget gateway, the handover request to a target base station;receiving, by the target gateway, a handover response sent by the targetbase station, where if the first service is supported by the target basestation, the handover response includes information about a handoverinstruction for the first service, and the handover instruction is usedto instruct the terminal device to hand over the first service to thetarget base station; and sending, by the target gateway, the handoverresponse to the source gateway.

According to a seventh aspect, the present patent application provides ahandover method, including: receiving, by a controller, a handoverrequest sent by a source base station, where the handover requestincludes information about a first service of a terminal device;sending, by the controller, the handover request to a target basestation; receiving, by the controller, a handover response sent by thetarget base station, where if the first service is supported by thetarget base station, the handover response includes information about ahandover instruction for the first service, and the handover instructionis used to instruct the terminal device to hand over the first serviceto the target base station; and sending, by the controller, the handoverresponse to the source base station.

With reference to the second, fifth, sixth or seventh aspect, in apossible implementation, the handover request further includesinformation about a second service of the terminal device; and if thesecond service is not supported by the target base station, the handoverresponse further includes information about an air interface resource ofthe second service, the air interface resource is determined by thetarget base station and on which interference coordination is performed,and the air interface resource is used by the terminal device and thesource base station to transmit the second service.

Furthermore, the handover request further includes quality of serviceinformation of the second service of the terminal device, and the airinterface resource is determined based on the quality of serviceinformation of the second service of the terminal device.

According to an eighth aspect, the present patent application provides abase station, including: a sending unit, configured to send a handoverrequest to a target base station, where the handover request includesinformation about a first service of a terminal device; and a receivingunit, configured to receive a handover response sent by the target basestation, where if the first service is supported by the target basestation, the handover response includes information about a handoverinstruction for the first service, and the handover instruction is usedto instruct the terminal device to hand over the first service from thebase station to the target base station; and the sending unit is furtherconfigured to send a handover response to the terminal device.

With reference to the eighth aspect, in a first possible implementationof the eighth aspect, the handover request further includes informationabout a second service of the terminal device; and if the second serviceis not supported by the target base station, the handover responsefurther includes information about an air interface resource of thesecond service, the air interface resource is determined by the targetbase station and on which interference coordination is performed, andthe air interface resource is used by the terminal device and the basestation to transmit the second service.

With reference to the first possible implementation of the eighthaspect, in a second possible implementation of the eighth aspect, thehandover request further includes quality of service information of thesecond service of the terminal device, and the air interface resource isdetermined by the target base station based on the quality of serviceinformation.

With reference to the eighth aspect, or the first or second possibleimplementation of the eighth aspect, in a third possible implementationof the eighth aspect, the receiving unit is further configured to obtaininformation about supported service of the target base station; and thatthe sending unit is configured to send the handover request to thetarget base station includes: if the target base station supports thefirst service, the sending unit is configured to send the handoverrequest to the target base station.

With reference to the third possible implementation of the eighthaspect, in a fourth possible implementation of the eighth aspect, thatthe receiving unit is further configured to obtain the information aboutthe at least one supported service of the target base station includes:the receiving unit is further configured to receive a measurement reportsent by the terminal device, where the measurement report includes theinformation about the at least one supported service of the target basestation.

With reference to the third possible implementation of the eighthaspect, in a fifth possible implementation of the eighth aspect, thatthe receiving unit is further configured to obtain the information aboutthe at least one supported service of the target base station includes:the receiving unit is further configured to receive the information thatis sent by a controller or the target base station and that is about theat least one supported service of the target base station.

With reference to any one of the eighth aspect, or the first to fifthpossible implementations of the eighth aspect, in a sixth possibleimplementation of the eighth aspect, the sending unit is specificallyconfigured to send the handover request to the target base station byusing the controller; and the receiving unit is specifically configuredto receive, by using the controller, the handover response sent by thetarget base station.

With reference to any one of the eighth aspect, or the first to fifthpossible implementations of the eighth aspect, in a seventh possibleimplementation of the eighth aspect, the sending unit is specificallyconfigured to send the handover request to the target base station byusing a source gateway and a target gateway; and the receiving unit isspecifically configured to receive, by using the source gateway and thetarget gateway, the handover response sent by the target base station.

According to a ninth aspect, the present patent application provides abase station, including: a receiving unit, configured to receive ahandover request sent by a source base station, where the handoverrequest includes information about a first service of a terminal device;and a sending unit, configured to send a handover response to the sourcebase station, where if the base station supports the first service, thehandover response includes information about a handover instruction forthe first service, and the handover instruction is used to instruct theterminal device to hand over the first service from the source basestation to the base station.

With reference to the ninth aspect, in a first possible implementationof the ninth aspect, the handover request further includes informationabout a second service of the terminal device; and if the base stationdoes not support the second service, the handover response furtherincludes information about an air interface resource of the secondservice, the air interface resource is determined by the base stationand on which interference coordination is performed, and the airinterface resource is used by the source base station and the terminaldevice to transmit the second service.

With reference to the first possible implementation of the ninth aspect,in a second possible implementation of the ninth aspect, the handoverrequest further includes quality of service information of the secondservice of the terminal device, and the air interface resource isdetermined by the base station based on the quality of serviceinformation.

With reference to any one of the ninth aspect, or the foregoing possibleimplementations of the ninth aspect, in a third possible implementationof the ninth aspect, the sending unit is further configured to send apath switch request to a gateway, where the path switch request includesthe information about the first service; and the receiving unit isfurther configured to receive a path switch request acknowledgement sentby the gateway.

With reference to any one of the ninth aspect, or the foregoing possibleimplementations of the ninth aspect, in a fourth possible implementationof the ninth aspect, that the receiving unit is configured to receivethe handover request sent by the source base station includes: thereceiving unit is configured to receive, by using a controller, thehandover request sent by the source base station; and that the sendingunit is configured to send the handover response to the source basestation includes: the sending unit is configured to send the handoverresponse to the source base station by using the controller.

With reference to any one of the ninth aspect, or the first to thirdpossible implementations of the ninth aspect, in a fifth possibleimplementation of the ninth aspect, that the receiving unit isconfigured to receive the handover request sent by the source basestation includes: the receiving unit is configured to receive, by usinga source gateway and a target gateway, the handover request sent by thesource base station; and that the sending unit is configured to send thehandover response to the source base station includes: the sending unitis configured to send the handover response to the source base stationby using the source gateway and the target gateway.

According to a tenth aspect, the present patent application provides aterminal device, including: a sending unit, configured to send ameasurement report to a source base station; and a receiving unit,configured to receive a handover response, where if a first service ofthe terminal device is supported by a target base station, the handoverresponse includes information about a handover instruction for the firstservice, and the handover instruction is used to instruct the terminaldevice to hand over the first service to the target base station.

With reference to the tenth aspect, in a first possible implementationof the tenth aspect, if a second service of the terminal device is notsupported by the target base station, the handover response furtherincludes information about an air interface resource of the secondservice, the air interface resource is determined by the target basestation and on which interference coordination is performed, and the airinterface resource is used by the terminal device and the source basestation to transmit the second service.

With reference to the first possible implementation of the tenth aspect,in a second possible implementation of the tenth aspect, the measurementreport includes information about supported service of the target basestation.

According to an eleventh aspect, the present patent application providesa gateway, including: a receiving unit, configured to receive a pathswitch request sent by a target base station, where the path switchrequest includes information about a first service of a terminal device;and a sending unit, configured to send a path switch requestacknowledgement to the target base station.

According to a twelfth aspect, the present patent application provides agateway, including: a receiving unit, configured to receive a handoverrequest sent by a source base station, where the handover requestincludes information about a first service of a terminal device; and asending unit, configured to send the handover request to a targetgateway, where the receiving unit is further configured to receive ahandover response sent by the target gateway, and if the first serviceis supported by a target base station, the handover response includesinformation about a handover instruction for the first service, and thehandover instruction is used to instruct the terminal device to handover the first service to the target base station; and the sending unitis further configured to send the handover response to the source basestation.

According to a thirteenth aspect, the present patent applicationprovides a gateway, including: a receiving unit, configured to receive ahandover request sent by a source gateway, the handover request includesinformation about a first service of a terminal device; and a sendingunit, configured to send the handover request to a target base station,where the receiving unit is further configured to receive a handoverresponse sent by the target base station, and if the first service issupported by the target base station, the handover response includesinformation about a handover instruction for the first service, and thehandover instruction is used to instruct the terminal device to handover the first service to the target base station; and the sending unitis further configured to send the handover response to the sourcegateway.

According to a fourteenth aspect, the present patent applicationprovides a controller, including: a receiving unit, configured toreceive a handover request sent by a source base station, where thehandover request includes information about a first service of aterminal device; and a sending unit, configured to send the handoverrequest to a target base station, where the receiving unit is furtherconfigured to receive a handover response sent by the target basestation, and if the first service is supported by the target basestation, the handover response includes information about a handoverinstruction for the first service, and the handover instruction is usedto instruct the terminal device to hand over the first service to thetarget base station; and the sending unit is further configured to sendthe handover response to the source base station.

With reference to the twelfth, thirteenth or fourteenth aspect, in apossible implementation, the handover request further includesinformation about a second service of the terminal device; and if thesecond service is not supported by the target base station, the handoverresponse further includes information about an air interface resource ofthe second service, the air interface resource is determined by thetarget base station and on which interference coordination is performed,and the air interface resource is used by the terminal device and thesource base station to transmit the second service. Further, thehandover request further includes quality of service information of thesecond service of the terminal device, and the air interface resource isdetermined based on the quality of service information of the secondservice of the terminal device.

According to a fifteenth aspect, the present patent application providesa base station, including: a transceiver; a memory, configured to storean instruction; and a processor, connected to the memory and thetransceiver, and configured to execute the instruction, so as to performthe following steps when executing the instruction: instructing thetransceiver to send a handover request to a target base station, wherethe handover request includes information about a first service of aterminal device; receiving, by using the transceiver, a handoverresponse sent by the target base station, where if the first service issupported by the target base station, the handover response includesinformation about a handover instruction for the first service, and thehandover instruction is used to instruct the terminal device to handover the first service to the target base station; and instructing thetransceiver to send a handover response to the terminal device.

With reference to the fifteenth aspect, in a first possibleimplementation of the fifteenth aspect, the handover request furtherincludes information about a second service of the terminal device; andif the second service is not supported by the target base station, thehandover response further includes information about an air interfaceresource of the second service, the air interface resource is determinedby the target base station and on which interference coordination isperformed, and the air interface resource is used by the source basestation and the terminal device to transmit the second service.

With reference to the first possible implementation of the fifteenthaspect, in a second possible implementation of the fifteenth aspect, thehandover request further includes quality of service information of thesecond service of the terminal device, and the air interface resource isdetermined by the target base station based on the quality of serviceinformation.

With reference to the fifteenth aspect, or the first or second possibleimplementation of the fifteenth aspect, in a third possibleimplementation of the fifteenth aspect, the processor further performsthe following steps when executing the instruction: obtaining, by usingthe transceiver, information about supported service of the target basestation; and if the target base station supports the first service,instructing the transceiver to send the handover request to the targetbase station.

With reference to the third possible implementation of the fifteenthaspect, in a fourth possible implementation of the fifteenth aspect, theprocessor performs the following step when executing the instruction:instructing the transceiver to receive a measurement report sent by theterminal device, where the measurement report includes the informationabout the at least one supported service of the target base station.

With reference to the fourth possible implementation of the fifteenthaspect, in a fifth possible implementation of the fifteenth aspect, theprocessor performs the following step when executing the instruction:instructing the transceiver to receive the information that is sent by acontroller or the target base station and that is about the at least onesupported service of the target base station.

With reference to any one of the fifteenth aspect, or the first to fifthpossible implementations of the fifteenth aspect, in a sixth possibleimplementation of the fifteenth aspect, the sending a handover requestto a target base station includes: sending the handover request to thetarget base station by using the controller; and the receiving ahandover response sent by the target base station includes: receiving,by using the controller, the handover response sent by the target basestation.

With reference to any one of the fifteenth aspect, or the first to fifthpossible implementations of the fifteenth aspect, in a seventh possibleimplementation of the fifteenth aspect, the sending a handover requestto a target base station includes: sending the handover request to thetarget base station by using a source gateway and a target gateway; andthe receiving a handover response sent by the target base stationincludes: receiving, by using the source gateway and the target gateway,the handover response sent by the target base station.

According to a sixteenth aspect, the present patent application providesa base station, including: a transceiver; a memory, configured to storean instruction; and a processor, connected to the memory and thetransceiver, and configured to execute the instruction, so as to performthe following steps when executing the instruction: receiving, by usingthe transceiver, a handover request sent by a source base station, wherethe handover request includes information about a first service of aterminal device; and instructing the transceiver to send a handoverresponse to the source base station, where if the base station supportsthe first service, the handover response includes information about ahandover instruction for the first service, and the handover instructionis used to instruct the terminal device to hand over the first servicefrom the source base station to the base station.

With reference to the sixteenth aspect, in a first possibleimplementation of the sixteenth aspect, the handover request furtherincludes information about a second service of the terminal device; andif the base station does not support the second service, the handoverresponse further includes information about an air interface resource ofthe second service, the air interface resource is determined by theprocessor and on which interference coordination is performed, and theair interface resource is used by the source base station and theterminal device to transmit the second service.

With reference to the first possible implementation of the sixteenthaspect, in a second possible implementation of the sixteenth aspect, thehandover request further includes quality of service information of thesecond service of the terminal device, and the air interface resource isdetermined by the base station based on the quality of serviceinformation.

According to a seventeenth aspect, the present patent applicationprovides a terminal device, including: a transceiver; a memory,configured to store an instruction; and a processor, connected to thememory and the transceiver, and configured to execute the instruction,so as to perform the following steps when executing the instruction:instructing the transceiver to send a measurement report to a sourcebase station; and receiving, by using the transceiver, a handoverresponse, where if a first service of the terminal device is supportedby a target base station, the handover response includes informationabout a handover instruction for the first service, and the handoverinstruction is used to instruct the terminal device to hand over thefirst service of the terminal device to the target base station.

With reference to the seventeenth aspect, in a first possibleimplementation of the seventeenth aspect, if a second service of theterminal device is not supported by the target base station, thehandover response further includes information about an air interfaceresource of the second service, the air interface resource is determinedby the target base station and on which interference coordination isperformed, and the air interface resource is used by the terminal deviceand the source base station to transmit the second service.

With reference to the first possible implementation of the seventeenthaspect, in a second possible implementation of the seventeenth aspect,the measurement report includes information about supported service ofthe target base station.

According to an eighteenth aspect, the present patent applicationprovides a gateway, including: a transceiver; a memory, configured tostore an instruction; and a processor, connected to the memory and thetransceiver, and configured to execute the instruction, so as to performthe following steps when executing the instruction: receiving, by usingthe transceiver, a path switch request sent by a target base station,where the path switch request includes information about a first serviceof a terminal device; and instructing the transceiver to send a pathswitch request acknowledgement to the target base station.

According to a nineteenth aspect, the present patent applicationprovides a gateway, including: a transceiver; a memory, configured tostore an instruction; and a processor, connected to the memory and thetransceiver, and configured to execute the instruction, so as to performthe following steps when executing the instruction: receiving, by usingthe transceiver, a handover request sent by a source base station, wherethe handover request includes information about a first service of aterminal device; instructing the transceiver to send the handoverrequest to a target gateway; receiving, by using the transceiver, ahandover response sent by the target gateway, where if the first serviceis supported by a target base station, the handover response includesinformation about a handover instruction for the first service, and thehandover instruction is used to instruct the terminal device to handover the first service to the target base station; and sending thehandover response to the source base station by using the transceiver.

According to a twentieth aspect, the present patent application providesa gateway, including: a transceiver; a memory, configured to store aninstruction; and a processor, connected to the memory and thetransceiver, and configured to execute the instruction, so as to performthe following steps when executing the instruction: receiving, by usingthe transceiver, a handover request sent by a source gateway, where thehandover request includes information about a first service of aterminal device; instructing the transceiver to send the handoverrequest to a target base station; receiving, by using the transceiver, ahandover response sent by the target base station, where if the firstservice is supported by the target base station, the handover responseincludes information about a handover instruction for the first service,and the handover instruction is used to instruct the terminal device tohand over the first service to the target base station; and sending thehandover response to the source gateway by using the transceiver.

According to a twenty-first aspect, the present patent applicationprovides a controller, including: a transceiver; a memory, configured tostore an instruction; and a processor, connected to the memory and thetransceiver, and configured to execute the instruction, so as to performthe following steps when executing the instruction: receiving, by usingthe transceiver, a handover request sent by a source base station, wherethe handover request includes information about a first service of aterminal device; instructing the transceiver to send the handoverrequest to a target base station; receiving, by using the transceiver, ahandover response sent by the target base station, where if the firstservice is supported by the target base station, the handover responseincludes information about a handover instruction for the first service,and the handover instruction is used to instruct the terminal device tohand over the first service to the target base station; and instructingthe transceiver to send the handover response to the source basestation.

With reference to the nineteenth, twentieth or twenty-first aspect, in apossible implementation, the handover request further includesinformation about a second service of the terminal device; and if thesecond service is not supported by the target base station, the handoverresponse further includes information about an air interface resource ofthe second service, the air interface resource is determined by thetarget base station and on which interference coordination is performed,and the air interface resource is used by the terminal device and thesource base station to transmit the second service. Further, thehandover request further includes quality of service information of thesecond service of the terminal device, and the air interface resource isdetermined based on the quality of service information of the secondservice of the terminal device.

According to a twenty-second aspect, the present patent applicationprovides a handover method, including: sending, by a source basestation, a handover request to a target base station, where the handoverrequest includes information about a second service of a terminaldevice; and receiving, by the source base station, a handover response,where if the second service is not supported by the target base station,the handover response includes information about an air interfaceresource of the second service, the air interface resource is determinedby the target base station and on which interference coordination isperformed, and the air interface resource is used by the source basestation and the terminal device to transmit the second service.

With reference to the twenty-second aspect, in a first possibleimplementation of the twenty-second aspect, the handover request furtherincludes quality of service information of the second service of theterminal device, and the air interface resource is determined based onthe quality of service information.

With reference to the twenty-second aspect or the first possibleimplementation of the twenty-second aspect, in a second possibleimplementation of the twenty-second aspect, if a first service issupported by the target base station, the handover request furtherincludes information about the first service of the terminal device; thehandover response further includes a handover instruction for the firstservice, and the handover instruction is used to instruct the terminaldevice to hand over the first service to the target base station; andthe method further includes: sending, by the source base station, thehandover response to the terminal device.

With reference to any one of the twenty-second aspect, or the foregoingpossible implementations of the twenty-second aspect, in a thirdpossible implementation of the twenty-second aspect, the method furtherincludes: obtaining, by the source base station, information aboutsupported service of the target base station; and the sending, by asource base station, a handover request to a target base stationincludes: if the target base station supports at least some services ofthe terminal device, sending, by the source base station, the handoverrequest to the target base station.

With reference to the third possible implementation of the twenty-secondaspect, in a fourth possible implementation of the twenty-second aspect,the obtaining, by the source base station, information about supportedservice of the target base station includes: receiving, by the sourcebase station, a measurement report sent by the terminal device, wherethe measurement report includes the information about the at least onesupported service of the target base station.

With reference to the third possible implementation of the twenty-secondaspect, in a fifth possible implementation of the twenty-second aspect,the obtaining, by the source base station, information about supportedservice of the target base station includes: receiving, by the sourcebase station, the information that is sent by a controller or the targetbase station and that is about the at least one supported service of thetarget base station.

With reference to any one of the twenty-second aspect, or the foregoingpossible implementations of the twenty-second aspect, in a sixthpossible implementation of the twenty-second aspect, the sending, by asource base station, a handover request to a target base stationincludes: sending, by the source base station, the handover request tothe target base station by using the controller; and the receiving, bythe source base station, a handover response sent by the target basestation includes: receiving, by the source base station by using thecontroller, the handover response sent by the target base station.

With reference to any one of the twenty-second aspect, or the foregoingpossible implementations of the twenty-second aspect, in a seventhpossible implementation of the twenty-second aspect, the sending, by asource base station, a handover request to a target base stationincludes: sending, by the source base station, the handover request tothe target base station by using a source gateway and a target gateway;and the receiving, by the source base station, a handover response sentby the target base station includes: receiving, by the source basestation by using the source gateway and the target gateway, the handoverresponse sent by the target base station.

According to a twenty-third aspect, the present patent applicationprovides a handover method, including: receiving, by a target basestation, a handover request sent by a source base station, where thehandover request includes information about a second service of aterminal device; sending, by the target base station, a handoverresponse, where if the target base station does not support the secondservice, the handover response includes information about an airinterface resource of the second service, the air interface resource isdetermined by the target base station and on which interferencecoordination is performed, and the air interface resource is used by thesource base station and the terminal device to transmit the secondservice.

With reference to the twenty-third aspect, in a first possibleimplementation of the twenty-third aspect, the handover request furtherincludes quality of service information of the second service of theterminal device, and the air interface resource is determined based onthe quality of service information of the second service of the terminaldevice.

With reference to the twenty-third aspect or the first possibleimplementation of the twenty-third aspect, in a second possibleimplementation of the twenty-third aspect, the handover request furtherincludes information about a first service of the terminal device; andif the target base station supports the first service, the handoverresponse further includes a handover instruction for the first service,and the handover instruction is used to instruct the terminal device tohand over the first service to the target base station.

With reference to the second possible implementation of the twenty-thirdaspect, in a third possible implementation of the twenty-third aspect,the method further includes: sending, by the target base station, a pathswitch request to a gateway, where the path switch request includes theinformation about the first service; and receiving, by the target basestation, a path switch request acknowledgement sent by the gateway.

With reference to any one of the twenty-third aspect, or the foregoingpossible implementations of the twenty-third aspect, in a fourthpossible implementation of the twenty-third aspect, the receiving, by atarget base station, a handover request sent by a source base stationincludes: receiving, by the target base station, the handover requestsent by a controller; and the sending, by the target base station, ahandover response to the source base station includes: sending, by thetarget base station, the handover response to the source base station byusing the controller.

With reference to any one of the twenty-third aspect, or the first tothird possible implementations of the twenty-third aspect, in a fifthpossible implementation of the twenty-third aspect, the receiving, by atarget base station, a handover request sent by a source base stationincludes: receiving, by the target base station by using a sourcegateway and a target gateway, the handover request; and the sending, bythe target base station, a handover response to the source base stationincludes: sending, by the target base station, the handover response byusing the source gateway and the target gateway.

According to a twenty-fourth aspect, the present patent applicationprovides a handover method, including: sending, by a terminal device, ameasurement report to a source base station; and receiving, by theterminal device, a handover response, where if a second service of theterminal device is not supported by a target base station, the handoverresponse includes information about an air interface resource of thesecond service, the air interface resource is determined by the targetbase station and on which interference coordination is performed, andthe air interface resource is used by the terminal device and the sourcebase station to transmit the second service.

With reference to the twenty-fourth aspect, in a first possibleimplementation of the twenty-fourth aspect, if a first service of theterminal device is supported by the target base station, the handoverresponse further includes a handover instruction for the first service,the handover instruction is used to instruct the terminal device to handover the first service to the target base station, and the first serviceis supported by the target base station.

With reference to the twenty-fourth aspect or the first possibleimplementation of the twenty-fourth aspect, in a second possibleimplementation of the twenty-fourth aspect, the measurement reportincludes information about supported service of the target base station.

According to a twenty-fifth aspect, the present patent applicationprovides a handover method, including: receiving, by a source gateway, ahandover request sent by a source base station, where the handoverrequest includes information about a second service of a terminaldevice; sending, by the source gateway, the handover request to a targetgateway; receiving, by the source gateway, a handover response sent bythe target gateway, where if the second service is not supported by atarget base station, the handover response includes information about anair interface resource of the second service, the air interface resourceis determined by the target base station and on which interferencecoordination is performed, and the air interface resource is used by theterminal device and the source base station to transmit the secondservice; and sending, by the source gateway, the handover response tothe source base station.

According to a twenty-sixth aspect, the present patent applicationprovides a handover method, including: receiving, by a target gateway, ahandover request sent by a source gateway, where the handover requestincludes information about a second service of a terminal device;sending, by the target gateway, the handover request to a target basestation; receiving, by the target gateway, a handover response sent bythe target base station, where if the second service is not supported bythe target base station, the handover response includes informationabout an air interface resource of the second service, the air interfaceresource is determined by the target base station and on whichinterference coordination is performed, and the air interface resourceis used by the terminal device and a source base station to transmit thesecond service; and sending, by the target gateway, the handoverresponse to the source gateway.

According to a twenty-seventh aspect, the present patent applicationprovides a handover method, including: receiving, by a controller, ahandover request sent by a source base station, where the handoverrequest includes information about a second service of a terminaldevice; sending, by the controller, the handover request to a targetbase station; receiving, by the controller, a handover response sent bythe target base station, where if the second service is not supported bythe target base station, the handover response includes informationabout an air interface resource of the second service, the air interfaceresource is determined by the target base station and on whichinterference coordination is performed, and the air interface resourceis used by the terminal device and the source base station to transmitthe second service; and sending, by the controller, the handoverresponse to the source base station.

With reference to the twenty-fifth or twenty-sixth or twenty-seventhaspect, in a possible implementation, the handover request furtherincludes quality of service information of the second service of theterminal device, and the air interface resource is determined based onthe quality of service information of the second service of the terminaldevice. Further, the handover request further includes information abouta first service of the terminal device; and if the first service issupported by the target base station, the handover response furtherincludes a handover instruction for the first service, and the handoverinstruction is used to instruct the terminal device to hand over thefirst service to the target base station.

According to a twenty-eighth aspect, the present patent applicationprovides a base station, including: a sending unit, configured to send ahandover request to a target base station, where the handover requestincludes information about a second service of a terminal device; and areceiving unit, configured to receive a handover response sent by thetarget base station, where if the second service is not supported by thetarget base station, the handover response includes information about anair interface resource of the second service, the air interface resourceis determined by the target base station and on which interferencecoordination is performed, and the air interface resource is used by thesource base station and the terminal device to transmit the secondservice; and the sending unit is further configured to send the handoverresponse to the terminal device.

With reference to the twenty-eighth aspect, in a first possibleimplementation of the twenty-eighth aspect, the handover request furtherincludes quality of service information of the second service of theterminal device, and the air interface resource is determined based onthe quality of service information.

With reference to the twenty-eighth aspect or the first possibleimplementation of the twenty-eighth aspect, in a second possibleimplementation of the twenty-eighth aspect, if a first service issupported by the target base station, the handover request furtherincludes information about the first service of the terminal device; thehandover response further includes a handover instruction for the firstservice, and the handover instruction is used to instruct the terminaldevice to hand over the first service to the target base station; andthe sending unit is further configured to send the handover response tothe terminal device.

With reference to any one of the twenty-eighth aspect, or the foregoingpossible implementations of the twenty-eighth aspect, in a thirdpossible implementation of the twenty-eighth aspect, the receiving unitis further configured to obtain information about supported service ofthe target base station; and that the sending unit is configured to sendthe handover request to the target base station includes: if the targetbase station supports at least some services of the terminal device, thesending unit is configured to send the handover request to the targetbase station.

With reference to any one of the twenty-eighth aspect, or the first tothird possible implementations of the twenty-eighth aspect, in a fourthpossible implementation of the twenty-eighth aspect, that the receivingunit is further configured to obtain the information about the at leastone supported service of the target base station includes: the receivingunit is further configured to receive a measurement report sent by theterminal device, where the measurement report includes the informationabout the at least one supported service of the target base station.

With reference to any one of the twenty-eighth aspect, or the first tothird possible implementations of the twenty-eighth aspect, in a fifthpossible implementation of the twenty-eighth aspect, that the receivingunit is further configured to obtain the information about the at leastone supported service of the target base station includes: the receivingunit is further configured to receive the information that is sent by acontroller or the target base station and that is about the at least onesupported service of the target base station.

With reference to any one of the twenty-eighth aspect, or the foregoingpossible implementations of the twenty-eighth aspect, in a sixthpossible implementation of the twenty-eighth aspect, that the sendingunit is configured to send the handover request to the target basestation includes: the sending unit is configured to send the handoverrequest to the target base station by using the controller; and that thereceiving unit is configured to receive the handover response sent bythe target base station includes: the receiving unit is configured toreceive, by using the controller, the handover response sent by thetarget base station.

With reference to any one of the twenty-eighth aspect, or the first tosixth possible implementations of the twenty-eighth aspect, in a seventhpossible implementation of the twenty-eighth aspect, that the sendingunit is configured to send the handover request to the target basestation includes: the sending unit is configured to send the handoverrequest to the target base station by using a source gateway and atarget gateway; and that the receiving unit is configured to receive thehandover response sent by the target base station includes: thereceiving unit is configured to receive, by using the source gateway andthe target gateway, the handover response sent by the target basestation.

According to a twenty-ninth aspect, the present patent applicationprovides a base station, including: a receiving unit, configured toreceive a handover request sent by a source base station, where thehandover request includes information about a second service of aterminal device; a sending unit, configured to send a handover responseto the source base station, where if the target base station does notsupport the second service, the handover response includes informationabout an air interface resource of the second service, the air interfaceresource is determined by the target base station and on whichinterference coordination is performed, and the air interface resourceis used by the source base station and the terminal device to transmitthe second service.

With reference to the twenty-ninth aspect, in a first possibleimplementation of the twenty-ninth aspect, the handover request furtherincludes quality of service information of the second service of theterminal device, and the air interface resource is determined based onthe quality of service information of the second service of the terminaldevice.

With reference to the first possible implementation of the twenty-ninthaspect, in a second possible implementation of the twenty-ninth aspect,the handover request further includes information about a first serviceof the terminal device; and if the target base station supports thefirst service, the handover response further includes a handoverinstruction for the first service, and the handover instruction is usedto instruct the terminal device to hand over the first service to thetarget base station.

With reference to the second possible implementation of the twenty-ninthaspect, in a third possible implementation of the twenty-ninth aspect,the sending unit is further configured to send a path switch request toa gateway, where the path switch request includes the information aboutthe first service; and the receiving unit is further configured toreceive a path switch request acknowledgement sent by the gateway.

With reference to any one of the twenty-ninth aspect, or the foregoingpossible implementations of the twenty-ninth aspect, in a fourthpossible implementation of the twenty-ninth aspect, that the receivingunit is configured to receive the handover request sent by the sourcebase station includes: the receiving unit is configured to receive, byusing a controller, the handover request sent by the source basestation; and that the sending unit is configured to send the handoverresponse to the source base station includes: the sending unit isconfigured to send the handover response to the source base station byusing the controller.

With reference to any one of the twenty-ninth aspect, or the first tothird possible implementations of the twenty-ninth aspect, in a fifthpossible implementation of the twenty-ninth aspect, that the receivingunit is configured to receive the handover request sent by the sourcebase station includes: the receiving unit is configured to receive, byusing a source gateway and a target gateway, the handover request sentby the source base station; and that the sending unit is configured tosend the handover response to the source base station includes: thesending unit is configured to send the handover response to the sourcebase station by using the source gateway and the target gateway.

According to a thirtieth aspect, the present patent application providesa terminal device, including: a sending unit, configured to send ameasurement report to a source base station; a receiving unit,configured to receive a handover response, where if a second service ofthe terminal device is not supported by a target base station, thehandover response includes information about an air interface resourceof the second service, the air interface resource is determined by thetarget base station and on which interference coordination is performed,and the air interface resource is used by the terminal device and thesource base station to transmit the second service.

With reference to the thirtieth aspect, in a first possibleimplementation of the thirtieth aspect, if a first service of theterminal device is supported by the target base station, the handoverresponse further includes a handover instruction for the first service,the handover instruction is used to instruct the terminal device to handover the first service to the target base station, and the first serviceis supported by the target base station.

With reference to the thirtieth aspect or the first possibleimplementation of the thirtieth aspect, in a second possibleimplementation of the thirtieth aspect, the measurement report includesinformation about supported service of the target base station.

According to a thirty-first aspect, the present patent applicationprovides a gateway, including: a receiving unit, configured to receive ahandover request sent by a source base station, where the handoverrequest includes information about a second service of a terminaldevice; and a sending unit, configured to send the handover request to atarget gateway, where the receiving unit is further configured toreceive a handover response sent by the target gateway, and if thesecond service is not supported by a target base station, the handoverresponse includes information about an air interface resource of thesecond service, the air interface resource is determined by the targetbase station and on which interference coordination is performed, andthe air interface resource is used by the terminal device and the sourcebase station to transmit the second service; and the sending unit isfurther configured to send the handover response to the source basestation.

According to a thirty-second aspect, the present patent applicationprovides a gateway, including: a receiving unit, configured to receive ahandover request sent by a source gateway, where the handover requestincludes information about a second service of a terminal device; and asending unit, configured to send the handover request to a target basestation, where the receiving unit is further configured to receive ahandover response sent by the target base station, and if the secondservice is not supported by the target base station, the handoverresponse includes information about an air interface resource of thesecond service, the air interface resource is determined by the targetbase station and on which interference coordination is performed, andthe air interface resource is used by the terminal device and a sourcebase station to transmit the second service; and the sending unit isfurther configured to send the handover response to the source gateway.

According to a thirty-third aspect, the present patent applicationprovides a controller, including: a receiving unit, configured toreceive a handover request sent by a source base station, where thehandover request includes information about a second service of aterminal device; and a sending unit, configured to send the handoverrequest to a target base station, where the receiving unit is furtherconfigured to: receive a handover response sent by the target basestation, and if the second service is not supported by the target basestation, the handover response includes information about an airinterface resource of the second service, the air interface resource isdetermined by the target base station and on which interferencecoordination is performed, and the air interface resource is used by theterminal device and the source base station to transmit the secondservice; and the sending unit is further configured to send the handoverresponse to the source base station.

With reference to the thirty-first, thirty-second or thirty-thirdaspect, in a first possible implementation of the thirty-third aspect,the handover request further includes quality of service information ofthe second service of the terminal device, and the air interfaceresource is determined based on the quality of service information ofthe second service of the terminal device. Further, the handover requestfurther includes information about a first service of the terminaldevice; and if the first service is supported by the target basestation, the handover response further includes a handover instructionfor the first service, and the handover instruction is used to instructthe terminal device to hand over the first service to the target basestation.

According to a thirty-fourth aspect, the present patent applicationprovides a base station, including: a transceiver; a memory, configuredto store an instruction; and a processor, connected to the memory andthe transceiver, and configured to execute the instruction, so as toperform the following steps when executing the instruction: instructingthe transceiver to send a handover request to a target base station,where the handover request includes information about a second serviceof a terminal device; receiving, by using the transceiver, a handoverresponse sent by the target base station, where if the second service isnot supported by the target base station, the handover response includesinformation about an air interface resource of the second service, theair interface resource is determined by the target base station and onwhich interference coordination is performed, and the air interfaceresource is used by the source base station and the terminal device totransmit the second service; and sending the handover response to theterminal device by using the transceiver.

With reference to the thirty-fourth aspect, in a first possibleimplementation of the thirty-fourth aspect, the handover request furtherincludes quality of service information of the second service of theterminal device, and the air interface resource is determined based onthe quality of service information.

With reference to the thirty-fourth aspect or the first possibleimplementation of the thirty-fourth aspect, in a second possibleimplementation of the thirty-fourth aspect, if a first service issupported by the target base station, the handover request furtherincludes information about the first service of the terminal device; thehandover response further includes a handover instruction for the firstservice, and the handover instruction is used to instruct the terminaldevice to hand over the first service to the target base station; andthe controller further performs the following step when executing theinstruction: sending the handover response to the terminal device byusing the transceiver.

With reference to any one of the thirty-fourth aspect, or the foregoingpossible implementations of the thirty-fourth aspect, in a thirdpossible implementation of the thirty-fourth aspect, the processorfurther performs the following step when executing the instruction:obtaining, by using the transceiver, information about supported serviceof the target base station; and the sending a handover request to atarget base station includes: if the target base station supports atleast some services of the terminal device, sending the handover requestto the target base station.

With reference to any one of the thirty-fourth aspect, or the first tothird possible implementations of the thirty-fourth aspect, in a fourthpossible implementation of the thirty-fourth aspect, the obtaininginformation about supported service of the target base station includes:receiving a measurement report sent by the terminal device, where themeasurement report includes the information about the at least onesupported service of the target base station.

With reference to any one of the thirty-fourth aspect, or the first tothird possible implementations of the thirty-fourth aspect, in a fifthpossible implementation of the thirty-fourth aspect, the obtaininginformation about supported service of the target base station includes:receiving the information that is sent by the controller or the targetbase station and that is about the at least one supported service of thetarget base station.

With reference to any one of the thirty-fourth aspect, or the foregoingpossible implementations of the thirty-fourth aspect, in a sixthpossible implementation of the thirty-fourth aspect, the sending ahandover request to a target base station includes: sending the handoverrequest to the target base station by using the controller; and thereceiving a handover response sent by the target base station includes:receiving, by using the controller, the handover response sent by thetarget base station.

With reference to any one of the thirty-fourth aspect, or the first tosixth possible implementations of the thirty-fourth aspect, in a seventhpossible implementation of the thirty-fourth aspect, the sending ahandover request to a target base station includes: sending the handoverrequest to the target base station by using a source gateway and atarget gateway; and the receiving a handover response sent by the targetbase station includes: receiving, by using the source gateway and thetarget gateway, the handover response sent by the target base station.

According to a thirty-fifth aspect, the present patent applicationprovides a base station, including: a transceiver; a memory, configuredto store an instruction; and a processor, connected to the memory andthe transceiver, and configured to execute the instruction, so as toperform the following steps when executing the instruction: instructingthe transceiver to receive a handover request sent by a source basestation, where the handover request includes information about a secondservice of a terminal device; and sending a handover response to thesource base station, where if the target base station does not supportthe second service, the handover response includes information about anair interface resource of the second service, the air interface resourceis determined by the target base station and on which interferencecoordination is performed, and the air interface resource is used by thesource base station and the terminal device to transmit the secondservice.

With reference to the thirty-fifth aspect, in a first possibleimplementation of the thirty-fifth aspect, the handover request furtherincludes quality of service information of the second service of theterminal device, and the air interface resource is determined based onthe quality of service information of the second service of the terminaldevice.

With reference to the first possible implementation of the thirty-fifthaspect, in a second possible implementation of the thirty-fifth aspect,the handover request further includes information about a first serviceof the terminal device; and if the target base station supports thefirst service, the handover response further includes a handoverinstruction for the first service, and the handover instruction is usedto instruct the terminal device to hand over the first service to thetarget base station.

With reference to the second possible implementation of the thirty-fifthaspect, in a third possible implementation of the thirty-fifth aspect,the processor further performs the following steps when executing theinstruction: sending a path switch request to a gateway by using thetransceiver, where the path switch request includes the informationabout the first service; and receiving, by using the transceiver, a pathswitch request acknowledgement sent by the gateway.

With reference to any one of the thirty-fifth aspect, or the foregoingpossible implementations of the thirty-fifth aspect, in a fourthpossible implementation of the thirty-fifth aspect, the receiving ahandover request sent by a source base station includes: receiving, byusing a controller, the handover request sent by the source basestation; and the sending a handover response to the source base stationincludes: sending the handover response to the source base station byusing the controller.

With reference to any one of the thirty-fifth aspect, or the first tothird possible implementations of the thirty-fifth aspect, in a fifthpossible implementation of the thirty-fifth aspect, the receiving ahandover request sent by a source base station includes: receiving, byusing a source gateway and a target gateway, the handover request sentby the source base station; and the sending a handover response to thesource base station includes: sending the handover response to thesource base station by using the source gateway and the target gateway.

According to a thirty-sixth aspect, the present patent applicationprovides a terminal device, including: a transceiver; a memory,configured to store an instruction; and a processor, connected to thememory and the transceiver, and configured to execute the instruction,so as to perform the following steps when executing the instruction:sending a measurement report to a source base station by using thetransceiver; and instructing the transceiver to receive a handoverresponse, where if a second service of the terminal device is notsupported by a target base station, the handover response includesinformation about an air interface resource of the second service, theair interface resource is determined by the target base station and onwhich interference coordination is performed, and the air interfaceresource is used by the terminal device and the source base station totransmit the second service.

With reference to the thirty-sixth aspect, in a first possibleimplementation of the thirty-sixth aspect, if a first service of theterminal device is supported by the target base station, the handoverresponse further includes a handover instruction for the first service,the handover instruction is used to instruct the terminal device to handover the first service to the target base station, and the first serviceis supported by the target base station.

With reference to the thirty-sixth aspect or the first possibleimplementation of the thirty-sixth aspect, in a second possibleimplementation of the thirty-sixth aspect, the measurement reportincludes information about supported service of the target base station.

According to a thirty-seventh aspect, the present patent applicationprovides a gateway, including: a transceiver; a memory, configured tostore an instruction; and a processor, connected to the memory and thetransceiver, and configured to execute the instruction, so as to performthe following steps when executing the instruction: instructing thetransceiver to receive a handover request sent by a source base station,where the handover request includes information about a second serviceof a terminal device; sending the handover request to a target gatewayby using the transceiver; instructing the transceiver to receive ahandover response sent by the target gateway, where if the secondservice is not supported by a target base station, the handover responseincludes information about an air interface resource of the secondservice, the air interface resource is determined by the target basestation and on which interference coordination is performed, and the airinterface resource is used by the terminal device and the source basestation to transmit the second service; and sending the handoverresponse to the source base station by using the transceiver.

According to a thirty-eighth aspect, the present patent applicationprovides a gateway, including: a transceiver; a memory, configured tostore an instruction; and a processor, connected to the memory and thetransceiver, and configured to execute the instruction, so as to performthe following steps when executing the instruction: instructing thetransceiver to receive a handover request sent by a source gateway,where the handover request includes information about a second serviceof a terminal device; sending the handover request to a target basestation by using the transceiver; instructing the transceiver to receivea handover response sent by the target base station, where if the secondservice is not supported by the target base station, the handoverresponse includes information about an air interface resource of thesecond service, the air interface resource is determined by the targetbase station and on which interference coordination is performed, andthe air interface resource is used by the terminal device and a sourcebase station to transmit the second service; and sending the handoverresponse to the source gateway by using the transceiver.

According to a thirty-ninth aspect, the present patent applicationprovides a controller, including: a transceiver; a memory, configured tostore an instruction; and a processor, connected to the memory and thetransceiver, and configured to execute the instruction, so as to performthe following steps when executing the instruction: instructing thetransceiver to receive a handover request sent by a source base station,where the handover request includes information about a second serviceof a terminal device; sending the handover request to a target basestation by using the transceiver; instructing the transceiver to receivea handover response sent by the target base station, where if the secondservice is not supported by the target base station, the handoverresponse includes information about an air interface resource of thesecond service, the air interface resource is determined by the targetbase station and on which interference coordination is performed, andthe air interface resource is used by the terminal device and the sourcebase station to transmit the second service; and sending the handoverresponse to the source base station by using the transceiver.

With reference to the thirty-seventh, thirty-eighth or thirty-ninthaspect, in a possible implementation, the handover request furtherincludes quality of service information of the second service of theterminal device, and the air interface resource is determined based onthe quality of service information of the second service of the terminaldevice. In another possible implementation, the handover request furtherincludes information about a first service of the terminal device; andif the first service is supported by the target base station, thehandover response further includes a handover instruction for the firstservice, and the handover instruction is used to instruct the terminaldevice to hand over the first service to the target base station.

According to a fortieth aspect, the present patent application providesa handover method, including: if a target base station supports aservice of a terminal device, sending, by a source base station, ahandover request to the target base station; receiving, by the sourcebase station, a handover response sent by the target base station; andsending, by the source base station, the handover response to theterminal device.

With reference to the fortieth aspect, in a first possibleimplementation of the fortieth aspect, the method further includes:receiving, by the source base station, a measurement report of theterminal device, where the measurement report includes information aboutsupported service of the target base station.

With reference to the fortieth aspect, in a second possibleimplementation of the fortieth aspect, the method further includes:receiving, by the source base station, information that is sent by acontroller or the target base station and that is about supportedservice of the target base station.

According to a forty-first aspect, the present patent applicationprovides a base station, including: a sending unit, configured to: if atarget base station supports all services of a terminal device, send ahandover request to the target base station; and a receiving unit,configured to receive a handover response sent by the target basestation, where the sending unit is further configured to send thehandover response to the terminal device.

With reference to the forty-first aspect, in a first possibleimplementation of the forty-first aspect, the receiving unit is furtherconfigured to: receive a measurement report of the terminal device,where the measurement report includes information about supportedservice of the target base station.

With reference to the forty-first aspect, in a second possibleimplementation of the forty-first aspect, the receiving unit is furtherconfigured to: receive information that is sent by a controller or thetarget base station and that is about supported service of the targetbase station.

According to a forty-second aspect, the present patent applicationprovides a base station, including: a transceiver; a memory, configuredto store an instruction; and a processor, connected to the memory andthe transceiver, and configured to execute the instruction, so as toperform the following steps when executing the instruction: if a targetbase station supports all services of a terminal device, instructing thetransceiver to send a handover request to the target base station; andreceiving, by using the transceiver, a handover response sent by thetarget base station; and instructing the transceiver to send thehandover response to the terminal device.

With reference to the forty-second aspect, in a first possibleimplementation of the forty-second aspect, the receiving unit is furtherconfigured to: the processor further performs the following step whenexecuting the instruction: receiving a measurement report of theterminal device by using the transceiver, where the measurement reportincludes information about supported service of the target base station.

With reference to the forty-second aspect, in a second possibleimplementation of the forty-second aspect, the processor furtherperforms the following step when executing the instruction: receiving,by using the transceiver, information that is sent by a controller orthe target base station and that is about supported service of thetarget base station.

According to a forty-third aspect, the present patent applicationprovides an interference coordination method, including: if a targetbase station does not support all services of a terminal device,sending, by a source base station, an interference coordination requestto the target base station; receiving, by the source base station, aninterference coordination response sent by the target base station,where the interference coordination response includes information aboutan air interface resource, the air interface resource is determined bythe target base station and on which interference coordination isperformed, and the air interface resource is used by the terminal deviceand the source base station to transmit a service; and sending, by thesource base station, the interference coordination response to theterminal device.

With reference to the forty-third aspect, in a first possibleimplementation of the forty-third aspect, the interference coordinationrequest includes quality of service information of the terminal device,and the air interface resource is determined by the target base stationbased on the quality of service information.

With reference to the forty-third aspect, in a second possibleimplementation of the forty-third aspect, the interference coordinationrequest includes request information of the air interface resource, andthe request information of the air interface resource is used toindicate information about an air interface resource on which the targetbase station is expected to perform interference coordination.

With reference to any one of the forty-third aspect, or the foregoingpossible implementations of the forty-third aspect, in a third possibleimplementation of the forty-third aspect, the method further includes:receiving, by the source base station, a measurement report of theterminal device, where the measurement report includes information aboutsupported service of the target base station.

With reference to any one of the forty-third aspect, or the first tothird possible implementations of the forty-third aspect, in a fourthpossible implementation of the forty-third aspect, the method furtherincludes: receiving, by the source base station, the information that issent by a controller or the target base station and that is about the atleast one supported service of the target base station.

With reference to any one of the forty-third aspect, or the foregoingpossible implementations of the forty-third aspect, in a fifth possibleimplementation of the forty-third aspect, the sending, by a source basestation, an interference coordination request to the target base stationincludes: sending, by the source base station, the interferencecoordination request to the target base station by using the controller;and the receiving, by the source base station, an interferencecoordination response sent by the target base station includes:receiving, by the source base station by using the controller, theinterference coordination response sent by the target base station.

With reference to any one of the forty-third aspect, or the first tofourth possible implementations of the forty-third aspect, in a sixthpossible implementation of the forty-third aspect, the sending, by asource base station, an interference coordination request to the targetbase station includes: sending, by the source base station, theinterference coordination request to the target base station by usingthe controller; and the receiving, by the source base station, aninterference coordination response sent by the target base stationincludes: receiving, by the source base station by using the controller,the interference coordination response sent by the target base station.

According to a forty-fourth aspect, the present patent applicationprovides an interference coordination method, including: receiving, by atarget base station, an interference coordination request from a sourcebase station; and sending, by the target base station, an interferencecoordination response to the source base station, where the interferencecoordination response includes information about an air interfaceresource, the air interface resource is determined by the target basestation and on which interference coordination is performed, and the airinterface resource is used by a terminal device and the source basestation to transmit a service.

With reference to the forty-fourth aspect, in a first possibleimplementation of the forty-fourth aspect, the interference coordinationrequest includes quality of service information of the terminal device,and the air interface resource is determined by the target base stationbased on the quality of service information.

With reference to the forty-fourth aspect, in a second possibleimplementation of the forty-fourth aspect, the interference coordinationrequest includes request information of the air interface resource, andthe request information of the air interface resource is used toindicate information about an air interface resource on which the targetbase station is expected to perform interference coordination.

With reference to any one of the forty-fourth aspect, or the foregoingpossible implementations of the forty-fourth aspect, in a third possibleimplementation of the forty-fourth aspect, the receiving, by a targetbase station, an interference coordination request from a source basestation includes: receiving, by the target base station, theinterference coordination request from the source base station by usinga controller; and the sending, by the target base station, aninterference coordination response to the source base station includes:sending, by the target base station, the interference coordinationresponse to the source base station by using the controller.

With reference to the forty-fourth aspect, or the first or secondpossible implementation ofthe forty-fourth aspect, in a fourth possibleimplementation of the forty-fourth aspect, the receiving, by a targetbase station, an interference coordination request from a source basestation includes: receiving, by the target base station, theinterference coordination request from the source base station by usinga source gateway and a target gateway; and the sending, by the targetbase station, an interference coordination response to the source basestation includes: sending, by the target base station, the interferencecoordination response to the source base station by using the targetgateway and the source gateway.

According to a forty-fifth aspect, the present patent applicationprovides an interference coordination method, including: sending, by aterminal device, a measurement report to a source base station; andreceiving, by the terminal device, an interference coordination responsesent by the source base station, where the interference coordinationresponse includes information about an air interface resource, the airinterface resource is determined by a target base station and on whichinterference coordination is performed, and the air interface resourceis used by the terminal device and the source base station to transmit aservice.

With reference to the forty-fifth aspect, in a first possibleimplementation of the forty-fifth aspect, the measurement reportincludes information about supported service of the target base station.

According to a forty-sixth aspect, the present patent applicationprovides an interference coordination method, including: receiving, by asource gateway, an interference coordination request sent by a sourcebase station; sending, by the source gateway, the interferencecoordination request to a target gateway; receiving, by the sourcegateway, an interference coordination response sent by the targetgateway, where the interference coordination response includesinformation about an air interface resource, the air interface resourceis determined by a target base station and on which interferencecoordination is performed, and the air interface resource is used by aterminal device and the source base station to transmit a service; andsending, by the source gateway, the interference coordination responseto the source base station.

According to a forty-seventh aspect, the present patent applicationprovides an interference coordination method, including: receiving, by atarget gateway, an interference coordination request sent by a sourcegateway; sending, by the target gateway, the interference coordinationrequest to a target base station; receiving, by the target gateway, aninterference coordination response sent by the target base station,where the interference coordination response includes information aboutan air interface resource, the air interface resource is determined bythe target base station and on which interference coordination isperformed, and the air interface resource is used by a terminal deviceand a source base station to transmit a service; and sending, by thetarget gateway, the interference coordination response to the sourcegateway.

With reference to the forty-sixth or forty-seventh aspect, in a possibleimplementation, the interference coordination request further includesquality of service information of the terminal device, and the airinterface resource is determined based on the quality of serviceinformation of the terminal device. In another possible implementation,the interference coordination request includes request information ofthe air interface resource, and the request information of the airinterface resource is used to indicate information about an airinterface resource on which the target base station is expected toperform interference coordination.

According to a forty-eighth aspect, the present patent applicationprovides a base station, including: a sending unit, configured to: if atarget base station does not support all services of a terminal device,send an interference coordination request to the target base station;and a receiving unit, configured to receive an interference coordinationresponse sent by the target base station, where the interferencecoordination response includes information about an air interfaceresource, the air interface resource is determined by the target basestation and on which interference coordination is performed, and the airinterface resource is used by the terminal device and the source basestation to transmit a service; and the sending unit is furtherconfigured to send, by the source base station, the interferencecoordination response to the terminal device.

With reference to the forty-eighth aspect, in a first possibleimplementation of the forty-eighth aspect, the interference coordinationrequest further includes quality of service information of a secondservice of the terminal device, and the air interface resource isdetermined based on the quality of service information.

With reference to the forty-eighth aspect, in a second possibleimplementation of the forty-eighth aspect, the interference coordinationrequest includes request information of the air interface resource, andthe request information of the air interface resource is used toindicate information about an air interface resource on which the targetbase station is expected to perform interference coordination.

With reference to any one of the forty-eighth aspect, or the foregoingpossible implementations of the forty-eighth aspect, in a third possibleimplementation of the forty-eighth aspect, the receiving unit is furtherconfigured to obtain information about supported service of the targetbase station; and that the sending unit is configured to send theinterference coordination request to the target base station includes:if the target base station does not support all the services of theterminal device, the sending unit is configured to send the interferencecoordination request to the target base station.

With reference to the third possible implementation of the forty-eighthaspect, in a fourth possible implementation of the forty-eighth aspect,that the receiving unit is further configured to obtain the informationabout the at least one supported service of the target base stationincludes: the receiving unit is further configured to obtain, by using ameasurement report, the information about the at least one supportedservice of the target base station.

With reference to the third possible implementation of the forty-eighthaspect, in a fifth possible implementation of the forty-eighth aspect,that the receiving unit is further configured to obtain the informationabout the at least one supported service of the target base stationincludes: the receiving unit is further configured to receive theinformation that is sent by a controller or the target base station andthat is about the at least one supported service of the target basestation.

With reference to any one of the forty-eighth aspect, or the foregoingpossible implementations of the forty-eighth aspect, in a sixth possibleimplementation of the forty-eighth aspect, that the sending unit isconfigured to send the interference coordination request to the targetbase station includes: the sending unit is configured to send theinterference coordination request to the target base station by usingthe controller; and that the receiving unit is configured to receive theinterference coordination response sent by the target base stationincludes: the receiving unit is configured to receive, by using thecontroller, the interference coordination response sent by the targetbase station.

With reference to any one of the forty-eighth aspect, or the first tosixth possible implementations of the forty-eighth aspect, in a seventhpossible implementation of the forty-eighth aspect, that the sendingunit is configured to send the interference coordination request to thetarget base station includes: the sending unit is configured to send theinterference coordination request to the target base station by using asource gateway and a target gateway; and that the receiving unit isconfigured to receive the interference coordination response sent by thetarget base station includes: the receiving unit is configured toreceive, by using the source gateway and the target gateway, theinterference coordination response sent by the target base station.

According to a forty-ninth aspect, the present patent applicationprovides a base station, including: a receiving unit, configured toreceive an interference coordination request sent by a source basestation; and a sending unit, configured to send an interferencecoordination response to the source base station, where the interferencecoordination response includes information about an air interfaceresource, the air interface resource is determined by the target basestation and on which interference coordination is performed, and the airinterface resource is used by a terminal device and the source basestation to transmit a service.

With reference to the forty-ninth aspect, in a first possibleimplementation of the forty-ninth aspect, the interference coordinationrequest includes quality of service information of the terminal device,and the air interface resource is determined by the target base stationbased on the quality of service information.

With reference to the forty-ninth aspect, in a second possibleimplementation of the forty-ninth aspect, the interference coordinationrequest includes request information of the air interface resource, andthe request information of the air interface resource is used toindicate information about an air interface resource on which the targetbase station is expected to perform interference coordination.

With reference to any one of the forty-ninth aspect, or the foregoingpossible implementations of the forty-ninth aspect, in a third possibleimplementation of the forty-ninth aspect, that the receiving unit isconfigured to receive the interference coordination request sent by thesource base station includes: the receiving unit is configured toreceive, by using a controller, the interference coordination requestsent by the source base station; and that the sending unit is configuredto send the interference coordination response to the source basestation includes: the sending unit is configured to send theinterference coordination response to the source base station by usingthe controller.

With reference to any one of the forty-ninth aspect, or the first andsecond possible implementations of the forty-ninth aspect, in a fourthpossible implementation of the forty-ninth aspect, that the receivingunit is configured to receive the interference coordination request sentby the source base station includes: the receiving unit is configured toreceive, by using a source gateway and a target gateway, theinterference coordination request sent by the source base station; andthat the sending unit is configured to send the interferencecoordination response to the source base station includes: the sendingunit is configured to send the interference coordination response to thesource base station by using the source gateway and the target gateway.

According to a fiftieth aspect, the present patent application providesa terminal device, including: a sending unit, configured to send ameasurement report to a source base station; and a receiving unit,configured to receive an interference coordination response, where theinterference coordination response includes information about an airinterface resource, the air interface resource is determined by a targetbase station and on which interference coordination is performed, andthe air interface resource is used by the terminal device and the sourcebase station to transmit a service.

With reference to the fiftieth aspect, in a first possibleimplementation of the fiftieth aspect, the measurement report includesinformation about supported service of the target base station.

According to a fifty-first aspect, the present patent applicationprovides a gateway, including: a receiving unit, configured to receivean interference coordination request sent by a source base station; anda sending unit, configured to send the interference coordination requestto a target gateway, where the receiving unit is further configured toreceive an interference coordination response sent by the targetgateway, for example, the interference coordination response includesinformation about an air interface resource, the air interface resourceis determined by a target base station and on which interferencecoordination is performed, and the air interface resource is used by aterminal device and the source base station to transmit a service; andthe sending unit is further configured to send the interferencecoordination response to the source base station.

According to a fifty-second aspect, the present patent applicationprovides a gateway, including: a receiving unit, configured to receivean interference coordination request sent by a source gateway; and asending unit, configured to send the interference coordination requestto a target base station, where the receiving unit is further configuredto receive an interference coordination response sent by the target basestation, the interference coordination response includes informationabout an air interface resource, the air interface resource isdetermined by the target base station and on which interferencecoordination is performed, and the air interface resource is used by aterminal device and a source base station to transmit a service; and thesending unit is further configured to send the interference coordinationresponse to the source gateway.

With reference to the fifty-first or fifty-second aspect, in a possibleimplementation, the interference coordination request further includesquality of service information of the terminal device, and the airinterface resource is determined based on the quality of serviceinformation of the terminal device. In another possible implementation,the interference coordination request includes request information ofthe air interface resource, and the request information of the airinterface resource is used to indicate information about an airinterface resource on which the target base station is expected toperform interference coordination.

According to a fifty-third aspect, the present patent applicationprovides a base station, including: a transceiver; a memory, configuredto store an instruction; and a processor, connected to the memory andthe transceiver, and configured to execute the instruction, so as toperform the following steps when executing the instruction: if a targetbase station does not support all services of a terminal device,instructing the transceiver to send an interference coordination requestto the target base station; receiving, by using the transceiver, aninterference coordination response sent by the target base station,where the interference coordination response includes information aboutan air interface resource, the air interface resource is determined bythe target base station and on which interference coordination isperformed, and the air interface resource is used by the terminal deviceand a source base station to transmit a service; and instructing thetransceiver to send the interference coordination response to theterminal device.

With reference to the fifty-third aspect, in a first possibleimplementation of the fifty-third aspect, the interference coordinationrequest includes quality of service information of the terminal device,and the air interface resource is determined by the target base stationbased on the quality of service information.

With reference to the fifty-third aspect, in a second possibleimplementation of the fifty-third aspect, the interference coordinationrequest includes request information of the air interface resource, andthe request information of the air interface resource is used toindicate information about an air interface resource on which the targetbase station is expected to perform interference coordination.

With reference to any one of the fifty-third aspect, or the foregoingpossible implementations of the fifty-third aspect, in a third possibleimplementation of the fifty-third aspect, the processor further performsthe following step when executing the instruction: receiving ameasurement report of the terminal device by using the transceiver,where the measurement report includes information about supportedservice of the target base station.

With reference to any one of the fifty-third aspect, or the first tothird possible implementations of the fifty-third aspect, in a fourthpossible implementation of the fifty-third aspect, the processor furtherperforms the following step when executing the instruction: receiving,by using the transceiver, the information that is sent by a controlleror the target base station and that is about the at least one supportedservice of the target base station.

According to a fifty-fourth aspect, the present patent applicationprovides a base station, including: a transceiver; a memory, configuredto store an instruction; and a processor, connected to the memory andthe transceiver, and configured to execute the instruction, so as toperform the following steps when executing the instruction: receiving,by using the transceiver, an interference coordination request from asource base station; and instructing the transceiver to send aninterference coordination response to the source base station, where theinterference coordination response includes information about an airinterface resource, the air interface resource is determined by thetarget base station and on which interference coordination is performed,and the air interface resource is used by a terminal device and thesource base station to transmit a service.

With reference to the fifty-fourth aspect, in a first possibleimplementation of the fifty-fourth aspect, the interference coordinationrequest includes quality of service information of the terminal device,and the air interface resource is determined by the target base stationbased on the quality of service information.

With reference to the fifty-fourth aspect, in a second possibleimplementation of the fifty-fourth aspect, the interference coordinationrequest includes request information of the air interface resource, andthe request information of the air interface resource is used toindicate information about an air interface resource on which the targetbase station is expected to perform interference coordination.

According to a fifty-fifth aspect, the present patent applicationprovides a terminal device, including: a transceiver; a memory,configured to store an instruction; and a processor, connected to thememory and the transceiver, and configured to execute the instruction,so as to perform the following steps when executing the instruction:instructing the transceiver to send a measurement report to a sourcebase station; and receiving, by using the transceiver, an interferencecoordination response sent by the source base station, where theinterference coordination response includes information about an airinterface resource, the air interface resource is determined by a targetbase station and on which interference coordination is performed, andthe air interface resource is used by the terminal device and the sourcebase station to transmit a service.

With reference to the fifty-fifth aspect, in a first possibleimplementation of the fifty-fifth aspect, the measurement reportincludes information about supported service of the target base station.

In still another aspect, the present patent application provides anetwork system, including the base station in the eighth aspect and thebase station in the ninth aspect. The network system may further includethe gateway in the eleventh aspect. The network system may furtherinclude the gateway in the twelfth aspect. The network system mayfurther include the gateway in the thirteenth aspect. The network systemmay further include the controller in the fourteenth aspect. The networksystem may further include the terminal device in the thirteenth aspect.

In still another aspect, the present patent application provides anetwork system, including the base station in the fifteenth aspect andthe base station in the sixteenth aspect. The network system may furtherinclude the gateway in the eighteenth aspect. The network system mayfurther include the gateway in the nineteenth aspect. The network systemmay further include the gateway in the twentieth aspect. The networksystem may further include the controller in the twenty-first aspect.The network system may further include the terminal device in theseventeenth aspect.

In still another aspect, the present patent application provides anetwork system, including the base station in the forty-eighth aspectand the base station in the forty-ninth aspect. The network system mayfurther include the gateway in the fifty-first aspect. The networksystem may further include the gateway in the fifty-second aspect. Thenetwork system may further include the terminal device in the fiftiethaspect.

In still another aspect, the present patent application provides acomputer storage medium, configured to store a computer softwareinstruction used by the foregoing base station or terminal device orgateway or controller, where the computer software instruction includesprograms used to perform the methods corresponding to the foregoingaspects.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic architectural diagram of a network slice;

FIG. 2 is a schematic diagram of a wireless communications systemaccording to an embodiment of the present patent application;

FIG. 3 is a schematic diagram of a base station according to anotherembodiment of the present patent application;

FIG. 4 is a schematic interactive diagram of a handover method accordingto another embodiment of the present patent application;

FIG. 5 is a schematic diagram of a source base station performinghandover decision according to another embodiment of the present patentapplication;

FIG. 6 is a schematic diagram of a target base station performingadmission control according to another embodiment of the present patentapplication;

FIG. 7 is a schematic interactive diagram of a handover method accordingto another embodiment of the present patent application;

FIG. 8 is a schematic interactive diagram of updating a resourceconfiguration according to another embodiment of the present patentapplication;

FIG. 9 is a schematic interactive diagram of a handover method accordingto another embodiment of the present patent application;

FIG. 10 is a schematic interactive diagram of updating a resourceconfiguration according to another embodiment of the present patentapplication;

FIG. 11 is a schematic interactive diagram of updating a network sliceconfiguration according to another embodiment of the present patentapplication;

FIG. 12 is a schematic interactive diagram of updating a network sliceconfiguration according to another embodiment of the present patentapplication;

FIG. 13 is a schematic interactive diagram of inter-cell interferencecoordination according to another embodiment of the present patentapplication;

FIG. 14 is a schematic interactive diagram of inter-cell interferencecoordination according to another embodiment of the present patentapplication;

FIG. 15 is a schematic interactive diagram of a handover methodaccording to another embodiment of the present patent application;

FIG. 16 is a schematic interactive diagram of an inter-cell interferencecoordination method according to another embodiment of the presentpatent application;

FIG. 17 is a schematic structural diagram of a base station according toanother embodiment of the present patent application;

FIG. 18 is a schematic structural diagram of a gateway according toanother embodiment of the present patent application;

FIG. 19 is a schematic structural diagram of a terminal device accordingto another embodiment of the present patent application;

FIG. 20 is a schematic structural diagram of a base station according toanother embodiment of the present patent application;

FIG. 21 is a schematic structural diagram of a gateway according toanother embodiment of the present patent application; and

FIG. 22 is a schematic structural diagram of a terminal device accordingto another embodiment of the present patent application.

DESCRIPTION OF EMBODIMENTS

Multiple embodiments are now described with reference to theaccompanying drawings, and same components in this specification areindicated by a same reference numeral. In the following description, forease of explanation, many specific details are provided to facilitatecomprehensive understanding of one or more embodiments. However,apparently, the embodiments may either not be implemented by using thesespecific details. In other examples, a well-known structure and deviceare shown in a form of block diagrams, to conveniently describe one ormore embodiments.

Terms such as “module” and “system” used in this specification are usedto indicate computer-related entities, hardware, firmware, combinationsof hardware and software, software, or software being executed. Inaddition, the embodiments are described with reference to a terminaldevice. The terminal device may also be referred to as a system, aterminal device unit, a terminal device station, a mobile station, amobile station, a remote station, a remote terminal device, a mobiledevice, a wireless communications device, a terminal device agent, aterminal device apparatus or UE (User Equipment, terminal device). Theterminal device may be a cellular phone, a cordless phone, a SIP(Session Initiation Protocol, Session Initiation Protocol) phone, a WLL(Wireless Local Loop, wireless local loop) station, a PDA (PersonalDigital Assistant, personal digital assistant), a hand-held devicehaving a wireless communication function, a computing device, or anotherprocessing device connected to a wireless modem.

In addition, the embodiments are described with reference to a basestation. The base station can be used to communicate with a mobiledevice. The base station may be a BTS (Base Transceiver Station, basetransceiver station) in GSM (Global System of Mobile Communication,Global System for Mobile Communications) or CDMA (Code Division MultipleAccess, Code Division Multiple Access); or may be an NB (NodeB, NodeB)in WCDMA (Wideband Code Division Multiple Access, Wideband Code DivisionMultiple Access); or may be an eNB or eNodeB (Evolutional Node B,evolved NodeB) in LTE (Long Term Evolution, Long Term Evolution), arelay station or an access point, a base station device in a futurenetwork, or the like.

In addition, aspects or features of the present patent application maybe implemented as a method, an apparatus or a product that uses standardprogramming and/or engineering technologies. The term “product” used inthis application covers a computer program that can be accessed from anycomputer-readable device, carrier or medium. For example, thecomputer-readable medium may include but is not limited to: a magneticstorage component (for example, a hard disk, a floppy disk or a magnetictape), an optical disc (for example, a CD (Compact Disk, compact disk)or a DVD (Digital Versatile Disk, digital versatile disk)), a smart cardand a flash memory component (for example, an EPROM (ErasableProgrammable Read-Only Memory, erasable programmable read-only memory),a card, a stick, or a key drive). In addition, various storage mediadescribed in this specification may indicate one or more devices and/orother machine-readable media that are configured to store information.The term “machine-readable media” may include but is not limited to aradio channel, and various other media that can store, contain, and/orcarry an instruction and/or data.

A network system shown in FIG. 1 includes a plurality of network slicesisolated from each other. A terminal device communicates with thenetwork slices by using a radio access network (radio access network,RAN). Each network slice includes a series of logical network functionsto correspondingly satisfy differentiated requirements of differentservice types. For example, in a massive machine-to-machinecommunication (Massive M2M) network slice, massive connections ofdevices need to be satisfied, but a quality of service (Quality ofService, QoS) requirement of a network is not high. For another example,in a mobile broadband (Mobile Broadband, MBB) network slice, ahigh-bandwidth requirement needs to be satisfied to satisfy arequirement of providing a high service rate. For still another example,in a critical machine type communication (Critical Machine TypeCommunication) network slice, a network needs to provide an ultra-lowlatency, but does not have a high-bandwidth requirement.

In the future, sensor communication will be deployed in automobiles toprovide unmanned driving. A latency needs to be strictly ensured, andcritical machine type communication network slices may be used toprovide services. Massively deployed water—meter reading sensors do nothave a high QoS requirement, and massive machine-to-machinecommunication network slices may be used to provide services.High-definition video services on mobile phones require high bandwidthsand high data rates, mobile broadband network slices may be used toprovide services.

In a wireless communications system, different network slices coverdifferent base stations. Herein, when a base station is covered by anetwork slice, the base station supports a service type corresponding tothe network slice. In contrast, when a base station is not covered by anetwork slice, the base station does not support a service typecorresponding to the network slice. In an actual communications system,some base stations support more service types corresponding to networkslices, and some base stations support fewer service types correspondingto network slices.

One network slice is formed by a group of logical network functions usedto support specific use cases. In a needed manner, the terminal deviceis guided to be connected to a correct slice. For example, a terminaldevice is guided to be connected to a correct slice based onsubscription or a type of the terminal device.

FIG. 2 shows a wireless communications system 200 according to theembodiments of this specification. The wireless communications system200 includes a plurality of base stations. In FIG. 2, an example inwhich the wireless communications system 200 includes two base stationsis used for description. The wireless communications system includes abase station AP 1 and a base station AP 2. The base station AP 1 and thebase station AP 2 may be base stations of a same type. For example, thebase station AP 1 and the base station AP 2 are both macro base stationsor both micro base stations. The base station AP 1 and the base stationAP 2 may alternatively be base stations of different types. For example,the base station AP 1 is a macro base station, and the base station A2is a micro base station. In the wireless communications system 200, Anetwork slice A may be a massive machine-to-machine communicationnetwork slice, and a network slice B is a mobile broadband networkslice. The network slice includes a series of logical network functionsto provide services of different types, so as to correspondingly satisfydifferentiated requirements of different service types. The networkslice A and the network slice B both cover the base station AP 1. Thebase station AP 1 may support transmission of both a massive M2M serviceand a mobile broadband service. The network slice A covers the basestation AP 2, but the network slice B does not cover the base station AP2. The base station AP 2 can only support transmission of a massive M2Mservice and does not support transmission of a mobile broadband service.The network slice B does not cover the base station AP 2 for severalreasons. For example, there is no interface between the base station AP2 and the network slice B. For another example, there is an interfacebut the network slice B is not instantiated. The foregoing only providesexamples for describing a relationship between a base station and anetwork slice.

According to another embodiment of the present patent application, FIG.3 is a schematic structural diagram of a base station. As shown in FIG.3, the base station 102 may include a plurality of antenna groups. Eachantenna group may include one or more antennas. For example, one antennagroup may include antennas 104 and 106, another antenna group mayinclude antennas 108 and 110, and an additional group may includeantennas 112 and 114. In FIG. 3, two antennas are shown for each antennagroup; however, more or fewer antennas may be used for each group. Thebase station 102 may additionally include a transmitter chain and areceiver chain, and a person of ordinary skill in the art may understandthat both the transmitter chain and the receiver chain may include aplurality of components related to signal sending and receiving, forexample, a processor, a modulator, a multiplexer, a demodulator, ademultiplexer, and an antenna.

The base station 102 may communicate with one or more terminal devices,for example, a terminal device 116 and a terminal device 122. However,it may be understood that the base station 102 may communicate with anyquantity of terminal devices similar to the terminal device 116 or 122.As shown in the figure, the terminal device 116 communicates with theantennas 112 and 114. The antennas 112 and 114 send information to theterminal device 116 by using a forward link 118, and receive informationfrom the terminal device 116 by using a reverse link 120. In addition,the terminal device 122 communicates with the antennas 104 and 106. Theantennas 104 and 106 send information to the terminal device 122 byusing a forward link 124, and receive information from the terminaldevice 122 by using a reverse link 126. In a frequency division duplex(Frequency Division Duplex, FDD) system, for example, a frequency banddifferent from that used by the reverse link 120 may be used for theforward link 118, and a frequency band different from that used by thereverse link 126 may be used for the forward link 124. In addition, in atime division duplex (Time Division Duplex, TDD) system, a commonfrequency band may be used for the forward link 118 and the reverse link120, and a common frequency band may be used for the forward link 124and the reverse link 126.

Each antenna group and/or an area designed for communication is referredto as a sector of the base station 102. For example, the antenna groupmay be designed to communicate with a terminal device in a sector of acoverage area of the base station 102. When the base station 102communicates with the terminal devices 116 and 122 respectively by usingthe forward links 118 and 124, a transmit antenna of the base station102 can improve signal-to-noise ratios of the forward links 118 and 124through beamforming. In addition, compared with a manner in which a basestation uses a single antenna to send signals to all terminal devices ofthe base station, when the base station 102 sends signals to therandomly scattered terminal devices 116 and 122 in related coverageareas through beamforming, mobile devices in neighboring cells aresubject to less interference.

In a given time, the base station 102, the terminal device 116 or theterminal device 122 may be a wireless communications sending apparatusand/or a wireless communications receiving apparatus. When sending data,the wireless communications sending apparatus can encode the data fortransmission. Specifically, the wireless communications sendingapparatus can obtain, for example, generate, receive from anothercommunications apparatus, or store in a memory, a particular quantity ofdata bits that need to be sent to the wireless communications receivingapparatus through a channel. Such data bits may be included in atransport block or a plurality of transport blocks of data, and thetransport block may be segmented to generate a plurality of code blocks.

In a current network (2G/3G/4G), each base station supports transmissionof all service types, and only strength of a reference signal betweencells is considered during existing mobility management. If a referencesignal received power of a target base station received by a terminaldevice is greater than a reference signal received power of a sourcebase station, a user obtains better channel quality at the target basestation than at the source base station, and the source base stationsends a handover request. If the target base station has sufficientresources, the target base station allows access by the terminal device.However, in a network slicing architecture, it is possible that a targetbase station cannot support all service types of a terminal device. Ifan existing handover method is still used, after being handed over tothe target base station, the terminal device cannot obtain acorresponding service, causing service interruption. Moreover, signalinggenerated during handover causes load to the system. In addition, duringexisting mobility management, only inter-cell handover is considered,and an inter-cell interference coordination technology is notconsidered.

FIG. 4 is a schematic interactive diagram of a handover method accordingto an embodiment of the present patent application. As shown in FIG. 4,the communication method includes the following steps:

401: A terminal device sends a measurement report to a source basestation. The source base station receives the measurement report sent bythe terminal device.

402: The source base station performs handover decision. The source basestation decides to send a handover request to a target base station.Handover decision performed by the source base station is furtherdescribed below in detail.

403: The source base station sends the handover request to the targetbase station. The target base station receives the handover request. Inthis embodiment, in some cases, the handover request containsinformation about a first service of the terminal device. In some otherembodiments, the handover request may further contain other informationsuch as quality of service (Quality of Service, QoS) information of theterminal device. The handover request may further include informationabout the target base station. The information about the target basestation may be an identifier (ID) of the target base station.

404: The target base station performs admission control after receivingthe handover request. The admission control may be performed based onthe information about the first service of the terminal device that iscontaind in the handover request and a service type or service typessupported by the target base station. Admission control performed by thetarget base station is further described below in detail.

405: The target base station sends a handover response to the sourcebase station. The handover response includes information about ahandover instruction for the first service. The handover instruction isused to instruct the terminal device to hand over the first service tothe target base station. The handover response may further containinformation of the source base station. The information of the sourcebase station may be an identifier (ID) of the source base station.

406: The source base station sends a handover response to the terminaldevice. The terminal device receives the handover response sent by thesource base station.

407: The terminal device sends a handover acknowledgement to the targetbase station.

408: The target base station sends a path switch request to a gateway.The gateway receives the path switch request. The path switch requestincludes the information about first service. The path switch request isused to notify the gateway that the first service of the terminal devicehas been handed over to the target base station. The gateway switches apath on a core network side of the first service of the terminal deviceto the target base station.

409: The gateway sends a path switch request acknowledgement to thetarget base station. The target base station receives the path switchrequest acknowledgement. The path switch request acknowledgement is afeedback for the path switch request, and is used to notify the targetbase station that switching of uplink and downlink paths on the corenetwork side of the first service of the terminal device has beencompleted.

410: The target base station provides the first service of the terminaldevice.

In 401, the measurement report may contain information about at leastone supported service of the target base station for the terminaldevice. The service support information may be in a status manner. Forexample, two bit identifiers are used to represent that the target basestation supports all, some, or none of service types of the terminaldevice. Such processing is simple and has low overheads. Alternatively,a plurality of bit identifiers are used to represent information about asupported service type of the target base station. Such processing ismore precise. The information about service support of the target basestation for the terminal device may be obtained by using broadcastinformation of the target base station. The source base station mayfurther obtain, in another manner, the information about the supportedservice type of the target base station. Details are further providedbelow.

FIG. 5 is a schematic flowchart of the source base station performinghandover decision in 402. The source base station needs to performhandover decision based on the supported service type of the target basestation. As shown in FIG. 5, after obtaining the service type supportedby the target base station, the source base station determines whetherthe target base station supports non of services of the terminal device.If the target base station can support at least one service of theterminal device, the source base station sends a handover request to thetarget base station. If the target base station cannot support anyservice of the terminal device, the source base station sends aninter-cell interference coordination (inter-cell interferencecoordination, ICIC) request to the target base station. The source basestation may further perform handover decision based on the measurementreport and radio resource management (radio resource management, RRM)information.

It should be noted that if the source base station determines that thetarget base station supports the service type of the terminal device,the information about the service included in the handover requestmessage sent by the source base station to the target base station couldbe avoided. The target base station does not need to consider servicetype information during admission control, and only considers a resourcestatus of the target base station. If the target base station has aresource, a handover response sent by the target base station to thesource base station includes information about a handover instruction.The handover instruction is used to instruct to hand over all servicetypes of the terminal device to the target base station. If the targetbase station has no resource, a handover response sent by the targetbase station to the source base station includes information ofrejecting handover.

If service types are corresponding to network slices in a one-to-onemanner, information about service in a handover request may be a networkslice identifier (ID). In other cases, the information about service maybe an independent information and may have a correspondence with anetwork slice ID.

In 404, a form of the handover instruction for the first service may bea first service identifier (ID) and a flag of the handover instruction.

Optionally, in 405, the handover response may further include acell-radio network temporary identifier (Cell-Radio Network TemporaryIdentifier, C-RNTI) of the terminal device in the target base station, asecurity algorithm of the target base station, and a dedicatedrandom-access preamble (Random-access Channel Preamble).

Steps 407 to 410 are performed only in case that at least one service ishanded over to the target base station.

Step 407 may include the following substeps:

The terminal device sends a synchronization request to the target basestation. The target base station receives the synchronization request.

The target base station sends uplink allocation information and timingadvance (Timing Advance, TA) information to the terminal device. Theterminal device receives the uplink allocation information and the TAinformation. The uplink allocation information includes information usedby the terminal device to send uplink data. The TA information is usedby the terminal device to perform time adjustment.

After being successfully connected to the target base station, theterminal device sends the handover acknowledgement to the target basestation. The target base station receives the handover acknowledgement.The handover acknowledgement includes a message of the C-RNTI. Thetarget base station may confirm, by using the C-RNTI, that the user is auser that is handed over.

In this embodiment, if all the services of the terminal device arehanded over to the target base station, the foregoing method may furtherinclude the following steps:

411: The target base station sends UE context release information to thesource base station. The source base station receives the UE contextrelease information. The UE context release information is used tonotify the source base station that the terminal device has been handedover to the target base station and trigger the source base station torelease an air interface resource. Step 411 only needs to be performedafter step 409.

412: The source base station releases context information of theterminal device.

If some of the services of the terminal device are handed over to thetarget base station, when the terminal device can be connected to onlyone base station at a same moment, the foregoing method may furtherinclude steps 411 and 412.

Because of mobility, a terminal device may move from a source basestation supporting all service types of the terminal device to a targetbase station that does not support all the service types of the terminaldevice. In a possible processing manner, a service of a service typethat the target base station does not support is interrupted for theterminal device. However, this causes a service interruption problem.This case is considered in the present patent application, andinter-cell interference coordination can be used for a service type thatis not supported by the target base station. This case is furtherdescribed below in detail.

In 403, the handover request may contain information about a secondservice of the terminal device. Certainly, the handover request mayfurther contain other information, for example, QoS information of thesecond service of the terminal device.

In 404, if the second service is not supported by the target basestation, when the target base station has air interface resources onwhich interference coordination can be performed, the handover responsesent by the target base station to the source base station containsinformation about an air interface resource of the second service. theair interface resource is determined by the target base station and onwhich interference coordination is performed. The information about theair interface resource is used to instruct the source base station toprovide the second service to the terminal device on the air interfaceresource.

In 405, the handover response correspondingly contains the informationabout the air interface resource of the second service.

In this case, the handover method may further include: 413, the sourcebase station provides the second service to the terminal device on theair interface resource on which interference coordination is performed.This step only needs to be performed after 406.

For the second service of the terminal device, a core network path doesnot need to be switched for the second service. When the source basestation still provides the second service to the terminal device, 411and 412 do not need to be performed.

In 404, that the target base station has the air interface resources onwhich interference coordination can be performed includes: the targetbase station has idle air interface resources on which interferencecoordination can be performed. In another case, if the target basestation is providing a latency insensitive service and the terminaldevice is a latency sensitive user, the target base station mayallocate, to the terminal device, air interface resources that areoriginally used for providing the latency insensitive service in a cell,to perform interference coordination. These air interface resources maybe air interface resources on which interference coordination can beperformed.

The inter-cell interference coordination is a technology of managingwireless air interface resources to implement inter-cell interferencecontrol. Specifically, as shown in FIG. 7, an interference base station,for example, an AP 2, performs transmission by using a power less than apreset value or does not perform transmission on some air interfaceresources. An interfered-with base station, for example, an AP 1,schedules a terminal device near the interference base station on theair interface resources, so as to reduce inter-cell interference fromthe interference base station to the terminal device. A power of thepreset value may be a normal transmit power. In this case, duringinterference coordination, transmission is performed by using a powerless than the normal transmit power or transmission is not performed onthe air interface resources.

An air interface resource includes a time resource and/or a frequencyresource. For example, in an LTE system, the air interface resourceincludes a plurality of resource blocks (Resource Block, RB). Each RB iscorresponding to one timeslot (slot) in a time domain, and iscorresponding to 12 continuous subcarriers in a frequency domain. For anair interface resource in this form, information about the air interfaceresource may indicate a plurality of RB blocks, and the informationabout the air interface resource may be extended in the time domain toindicate, for example, N slots and 12 continuous subcarriers, or may beextended in the frequency domain to indicate, for example, one slot and12*M subcarriers, or may be simultaneously extended in both the timedomain and the frequency domain to indicate, for example, N slots and12*M subcarriers. N and M are positive integers greater than 0.Certainly, in a future communications system, the air interface resourcemay further be embodied in other forms.

If the handover request contains the QoS information of the secondservice of the terminal device, the target base station calculates,based on the QoS information, a quantity of air interface resourcesneeded to satisfy a QoS requirement of the terminal device, and thenchooses corresponding air interface resources. In this way, airinterface resources can be dynamically determined, and utilization ofthe air interface resources is high. If a manner of reserving airinterface resources is used, there may be two results: air interfaceresources are insufficient or air interface resources are excessive.When air interface resources are insufficient, reserved air interfaceresources are not sufficient to satisfy a QoS requirement of theterminal device. When air interface resources are excessive, a quantityof reserved air interface resources is greater than a quantity of airinterface resources for satisfying a QoS requirement of the terminaldevice. The target base station cannot perform transmission on thereserved air interface resources, resulting in a waste of air interfaceresources.

FIG. 6 is a schematic flowchart of a target base station performingadmission control. If a handover request contains a service type of aterminal device, the target base station needs to perform admissioncontrol depending on whether the service type of the terminal device issupported. As shown in FIG. 6, after receiving a handover request, thetarget base station determines whether the target base station supportsall service types of a terminal device. If the target base stationsupports all the service types of the terminal device and the targetbase station has sufficient resources, a handover response sent by thetarget base station contains information about a handover instructionfor all services. The information instructs the terminal device to handover all the services from a source base station to the target basestation. If the target base station does not have sufficient resourcesto serve the terminal device, a handover response sent by the targetbase station to a source base station contains information of rejectinghandover or information about handover of at least one service of allthe services.

If the target base station does not support all the service types of theterminal device, it means that the target base station supports someservice types of the terminal device.

If the terminal device can be simultaneously connected to two basestations, a resource status of the target base station may beconsidered. When the target base station has sufficient resources tosimultaneously perform handover and ICIC, the target base stationperforms handover on a supported service and perform ICIC on a servicethat is not supported. When the target base station has some resourcesthat can only be used to perform handover or perform ICIC, a priority ofa service type is considered. If supported service of the target basestation has a relatively high priority, the target base station onlyperforms handover on the supported service. If a service that the targetbase station does not support has a relatively high priority, the targetbase station only performs ICIC on the service that the target basestation does not support. When the target base station has no resources,the target base station performs neither handover nor ICIC.

If the terminal device cannot be simultaneously connected to two basestations, a resource status of the target base station may beconsidered. When the target base station has sufficient resources, apriority of a service type is considered. If supported service of thetarget base station has a relatively high priority, the target basestation only performs handover on the supported service. If a servicethat the target base station does not support has a relatively highpriority, the target base station only performs ICIC on the service thatthe target base station does not support. When the target base stationhas no resources, the target base station performs neither handover norICIC.

Based on these several cases, the handover response contains variedinformation. If the target base station performs handover on supportedservice of the target base station, the handover response contains ahandover instruction for the service. If the target base stationperforms ICIC on a service that the target base station does notsupport, the handover response contains an indication of an airinterface resource of the service. If the target base station rejectshandover, the handover response contains information of rejectinghandover.

A handover request contains a service type, so that the target basestation can accurately perform admission control and determine whetherthe target base station needs to accept a handover. A serviceinterruption probability of a terminal device is reduced. An existinghandover request does not contain service type information. When thetarget base station has a resource, even if the target base stationcannot provide services of some service types, the target base stationshould admit to serve the user during admission control. However, afterhandover, the target base station cannot provide a service of acorresponding type. As a result, service interruption occurs because ofinaccurate admission control. However, in the present patentapplication, a handover request contains a service type. Duringadmission control, the target base station may know whether the targetbase station supports a current service of a user. The target basestation admit to serve the user if the target base station has resourcesand supports all current services of the user. In this way, serviceinterruption can be avoided. In a scenario of a network slice, ahandover request contains a service type, and the target base stationconsiders a service type during admission control. In this way, aservice interruption problem caused by mobility of a terminal device canbe resolved to some extent. Further, the source base station alsoconsiders a service type during handover decision. The source basestation sends a handover request to the target base station only whenthe target base station supports at least some service types of theterminal device. The source base station no longer sends a handoverrequest when the target base station supports none of services of thesource base station, so that inter-system signaling interaction isreduced.

FIG. 2 is used as an example. Referring to this embodiment, if thetarget base station is an AP 2, the AP 2 supports a service typecorresponding to a network slice A but does not support a service typecorresponding to a network slice B. In this case, a second servicecorresponding to the network slice B continues to reside in the sourcebase station. A first service corresponding to the network slice A maybe handed over to the target base station.

In conventional mobility handover, after handover is completed, thesource base station releases context information of a terminal deviceand an air interface resource allocated to the terminal device. In thisembodiment, after handover is completed, the source base stationdetermines, based on a specific condition, whether to release thecontext information of the terminal device. If the source base stationstill needs to provide a second service to the terminal device, thecontext information of the terminal device may be reserved. If thesource base station does not need to provide any service to the terminaldevice, the context information of the terminal device may be released.

During mobility management of the present patent application, if ICIC isperformed, the terminal device still resides in the source base station,and specifically services are provided to the terminal device on someair interface resources. The target base station performs transmissionby using a power less than a normal transmit power or does not performtransmission on the air interface resources. In this way, the sourcebase station is subject to less interference, and a service interruptionproblem is avoided to some extent, so that an interruption probabilitycaused by mobility of a terminal device is reduced. In addition, theterminal device resides in the source base station and does notnecessarily need to be handed over to the target base station, so that aquantity of handovers is reduced.

Further analysis is provided below with reference to a more specificscenario. In the specific scenario, a source base station and a targetbase station may be respectively macro base stations or micro basestations. A macro base station has a relatively large coverage radiusthat is usually approximately 500 m to 1500 m. A micro base station isusually a base station that has a relatively small transmit power andthat is repeatedly deployed within a coverage area of a macro basestation to resolve a traffic requirement or a coverage hole in a hotspotarea, and usually has a coverage radius of approximately tens of meters.

It is assumed that the source base station is a macro base station andthe target base station is a micro base station within a coverage areaof the source base station. The target base station does not support allservices of a terminal device. In this case, as the terminal deviceapproaches the target base station and leaves the target base station,when the solution is used, the terminal device may remain residing inthe source base station to obtain desirable services without needinghandover, so that a quantity of handovers is reduced. In a conventionalsolution, because the target base station does not support all theservices of the terminal device, the target base station refuses, duringhandover, to accept a service that the target base station does notsupport. Moreover, due to interference from the target base station tothe source base station as the terminal device moves to the target basestation, the source base station cannot provide services to the terminaldevice, resulting in service interruption of the terminal device.

If the target base station and the source base station are both macrobase stations, or the target base station and the source base stationare both micro base stations, or the source base station is a micro basestation and the target base station is a macro base station, because thetarget base station performs transmission by using a power less than anormal transmit power on an air interface resource or does not performtransmission on an air interface resource, interference to the sourcebase station is reduced. Compared with an existing solution, in thisapplication, the source base station can provide services to a terminaldevice for a longer time. In this prolonged time, a service of theterminal device may have been transmitted, or even if the service hasnot been transmitted, a time that the network provides a service to theterminal device can be prolonged, so that the service can be interruptedlater. This improves service experience of the terminal device.

In the present patent application, the source base station initiateshandover, and the terminal device does not need to be changed. Inaddition, a Radio Air Interface Resource Control (Radio ResourceControl, RRC) link, random access, and synchronization do not need to beestablished in a scenario in which the terminal device cannot be handedover to the target base station, so that random-access air interfaceresources are saved.

In the present patent application, if the target base station has no airinterface resource to perform handover, and the target base station hasno air interface resource for interference coordination, for example,the target base station is fully loaded, the target base station decidesto reject handover and does not perform interference coordination on theterminal device. In this case, the handover response sent by the targetbase station to the source base station contains failure information.

FIG. 8 is a schematic interactive diagram of a handover method accordingto another embodiment of the present patent application. As shown inFIG. 8, the communication method includes the following steps:

801: When a terminal device finishes communication with a source basestation or a terminal device leaves a coverage area of a target basestation, the source base station sends an air interface resourceconfiguration update request to the target base station. The airinterface resource configuration update request contains informationabout an air interface resource. The information about the air interfaceresource in the air interface resource configuration update request isused to indicate that the target base station does not need to performinterference coordination on the air interface resource.

802: The target base station receives the air interface resourceconfiguration update request. The target base station no longer performsinterference coordination on the air interface resource. The target basestation sends an air interface resource configuration updateacknowledgement to the source base station. The source base stationreceives the air interface resource configuration update acknowledgementsent by the target base station. The air interface resourceconfiguration update acknowledgement is used to indicate that the targetbase station no longer performs interference coordination on the airinterface resource.

In the present patent application, after the terminal device has left orthe terminal device finishes communication with the source base station,the target base station is notified that no interference coordinationneeds to be performed on the air interface resource. The target basestation may reuse the air interface resource to provide a service to aterminal device within the coverage area of target base station, therebyimproving utilization of air interface resources.

FIG. 9 is a schematic interactive diagram of a handover method accordingto another embodiment of the present patent application. In theembodiment shown in FIG. 4, the source base station and the target basestation directly transfer handover signaling. In this embodiment, asource base station and a target base station forward handover signalingby using a controller. A handover request and a handover response inthis embodiment may replace the handover request and the handoverresponse between the source base station and the target base station inFIG. 4. As shown in FIG. 9, the communication method includes thefollowing steps:

901: The source base station sends a handover request to the controller.The controller receives the handover request. The controller may be anetwork slice controller or a controller in another form, for example, amobility management entity (mobility management entity, MME), a gateway,or another type of controller. In this embodiment, the handover requestcontains information about service of a terminal device and informationabout the target base station. The information about the target basestation may be a target base station list or an identifier (identifier,ID) of a specific target base station. The information about the targetbase station may be obtained through interaction between the basestations or obtained by using a core network.

902: The controller sends a handover request to the target base stationbased on the information about the target base station after receivingthe handover request. The target base station receives the handoverrequest. If the information about the target base station is the targetbase station list, the controller selects one target base station andsends the handover request to the target base station. The controllermay select one target base station from a perspective of utilityoptimization based on network conditions known by the controller, forexample, load of base stations, and service types supported by the basestations. For example, a target base station having lowest load, atarget base station whose supported service type is closest to a servicetype of the terminal device, or a target base station that has lowestload and whose supported service type is closest to a service type ofthe terminal device is selected from the target base station list. Ifthe information about the target base station is the identifier of thetarget base station, the controller sends the handover request to thetarget base station corresponding to the identifier of the target basestation.

903: The target base station sends a handover response to thecontroller. The controller receives the handover response.

904: The controller sends a handover response to the source basestation. The source base station receives the handover response.

If there is no interface between the base stations or a handover requestfails to be directly sent between the base stations, this embodiment maybe used to complete handover.

FIG. 10 is a schematic interactive diagram of a handover methodaccording to another embodiment of the present patent application. Inthe embodiment shown in FIG. 8, the source base station and the targetbase station directly transfer signaling about an air interface resourceconfiguration. In this embodiment, a source base station and a targetbase station forward signaling about an air interface resourceconfiguration by using a controller. As shown in FIG. 10, thecommunication method includes the following steps:

1001: The source base station sends an air interface resourceconfiguration update request to the controller. The controller receivesthe air interface resource configuration update request. The airinterface resource configuration update request contains informationabout an air interface resource and information about the target basestation.

1002: The controller sends the air interface resource configurationupdate request to the target base station. The air interface resourceconfiguration update request contains the information about the airinterface resource. The target base station receives the air interfaceresource configuration update request. The target base station no longerperforms interference coordination.

1003: The target base station sends an air interface resourceconfiguration update acknowledgement to the controller. The controllerreceives the air interface resource configuration updateacknowledgement. The air interface resource configuration updateacknowledgement is used to indicate that the target base station nolonger performs interference coordination on the air interface resource.

1004: The controller sends the air interface resource configurationupdate acknowledgement to the source base station. The source basestation receives the air interface resource configuration updateacknowledgement sent by the controller.

If there is no interface between the base stations or an air interfaceresource configuration fails to be directly updated between the basestations, this embodiment may be used to complete air interface resourceconfiguration update.

If ICIC is performed in the embodiments, the embodiments may further becombined with the embodiment shown in FIG. 8 or FIG. 10.

FIG. 11 is a schematic interactive diagram of base stations when asource base station obtains a supported service type of a target basestation according to an embodiment of the present patent application. Asshown in FIG. 11, the handover method may include the following steps:

1101: The target base station sends a network slice configuration updaterequest to the source base station. The source base station receives thenetwork slice configuration update request. The network sliceconfiguration update request contains the supported service type of thetarget base station.

1102: After receiving the network slice configuration update requestsent by the target base station, the source base station saves thesupported service type of the target base station, and sends networkslice configuration update acknowledgement signaling to the target basestation.

A network slice configuration update request may be initiated by anybase station, not limited to being initiated by the target base stationto the source base station. When being covered by a new network slice,the target base station may initiate a network slice configurationupdate request to the source base station.

FIG. 12 is another schematic interactive diagram of base stations, sothat a source base station obtains a supported service type of a targetbase station. Specifically, the handover method may further include thefollowing steps:

1201: The target base station sends a network slice configuration updaterequest to a controller. The controller receives the network sliceconfiguration update request.

1202: After receiving the network slice configuration update request,the controller sends the network slice configuration update request tothe source base station. The source base station receives the networkslice configuration update request.

1203: After receiving the network slice configuration update requestsent by the target base station, the source base station saves thesupported service type of the target base station, and sends networkslice configuration update acknowledgement signaling to the controller.The controller receives the network slice configuration updateacknowledgement signaling.

1204: After receiving the network slice configuration updateacknowledgement signaling, the controller sends the network sliceconfiguration update acknowledgement signaling to the source basestation.

If there is no interface between the base stations or a network sliceconfiguration fails to be directly updated between the base stations,this embodiment may be used to complete network slice configurationupdate.

FIG. 13 is a schematic interactive diagram of an inter-cell interferencecoordination method according to another embodiment of the presentpatent application. In this embodiment, a source base station finds thata target base station does not support all service types of a terminaldevice. In this case, the source base station directly sends an ICICrequest to the target base station to request the target base station toperform interference coordination on the terminal device. As shown inFIG. 13, the communication method includes the following steps:

1301 is basically the same as 401.

1302: The source base station performs ICIC decision. The source basestation decides to send the ICIC request to the target base station.

1303: The source base station sends the ICIC request to the target basestation, and the target base station receives the ICIC request. In acase, the ICIC request may contain interference coordinationinformation. The interference coordination information includesinformation about an air interface resource that is needed by the sourcebase station and on which inter-cell interference coordination isperformed. The information about the resource may be specifically a timefrequency resource block of the inter-cell interference coordination, ormay be a size of a needed time frequency resource block on whichinter-cell interference coordination is performed, or may be in anotherform. The ICIC request may contain QoS information of the terminaldevice. After receiving the QoS information, the target base stationdetermines a needed air interface resource based on the QoS information.Refer to the foregoing description.

1304: The target base station performs ICIC control after receiving theICIC request. If the target base station has an idle air interfaceresource for interference coordination, an ICIC response sent by thetarget base station to the source base station contains informationabout an air interface resource. The information about the air interfaceresource is used to indicate that the target base station performs ICICon the air interface resource.

1305: The target base station sends the ICIC response to the source basestation. The source base station receives the ICIC response. The ICICresponse contains the information about the air interface resource.

1306: The source base station sends the ICIC response to the terminaldevice. The terminal device receives the ICIC response.

1307 is basically the same as 413.

In 1302, ICIC decision is triggered by a single measurement report ofthe terminal device. The measurement report is sent as the terminaldevice moves. Optionally, in 1303, the ICIC request may further containinformation about a first service of the terminal device.Correspondingly, in 1304, when the target base station does not have anidle air interface resource for interference coordination, the targetbase station needs to consider the first service of the terminal. If apriority of the first service is higher than that of a service currentlyprovided by the target base station, the ICIC response sent by thetarget base station to the source base station contains informationabout an air interface resource. If a priority of the first service isnot higher than that of a service currently provided by the target basestation, the ICIC response sent by the target base station to the sourcebase station contains information of rejecting ICIC.

Conventional ICIC in LTE is usually periodically triggered or triggeredbased on statistical information. The statistical information may be achange of a quantity of edge users. In the present patent application,the measurement report is triggered during the movement of the terminal.The source base station needs to consider a service type when performinghandover decision. If the target base station does not support allservices of the terminal device, the source base station decides to sendthe ICIC request to the target base station.

FIG. 14 is a schematic interactive diagram of an inter-cell interferencecoordination method according to another embodiment of the presentpatent application. In this embodiment, a source base station and atarget base station forward handover signaling by using a controller. Asshown in FIG. 14, the communication method includes the following steps:

1401 is basically the same as 1301.

1402 is basically the same as 1302.

1403: The source base station sends the ICIC request to the controller.The controller receives the ICIC request. The ICIC request may containinterference coordination information. Refer to the foregoingdescription for the interference coordination information. In thisembodiment, a handover request further needs to contain informationabout the target base station. The information about the target basestation may be a target base station list or an ID of a specific targetbase station. Refer to the foregoing description for the informationabout the target base station.

1404: The controller sends the ICIC request to the target base stationbased on the information about the target base station after receivingthe ICIC request. The target base station receives the handover request.Refer to the foregoing description for selection of a target basestation based on the information about the target base station.

1405 is basically the same as 1304.

1406: The target base station sends a handover response to thecontroller, and the controller receives the handover response.

1407: The controller sends the handover response to the source basestation. The source base station receives the handover response.

1408 and 1409 are basically the same as 1306 and 1307.

The source base station and the target base station may be administratedby different gateways. Mobility management of the terminal device inthis case is further described below. If direct handover between thesource base station and the target base station fails, the followingembodiment may be used. FIG. 15 is a schematic interactive diagram of ahandover method according to another embodiment of the present patentapplication. The embodiment shown in FIG. 15 and the embodiment in FIG.4 have similar application scenarios. The same or similar parts are nolonger described in detail. As shown in FIG. 15, the communicationmethod includes the following steps:

1501 is basically the same as 401.

1502 is similar to 402, and the source base station decides to send ahandover request to a source gateway.

1503: The source base station sends the handover request to the sourcegateway. The source gateway receives the handover request. The handoverrequest further includes a tracking area identifier used to assist thesource gateway in selecting a suitable target gateway.

1504: The source gateway selects a target gateway based on the trackingarea identifier. The source gateway sends a handover request to thetarget gateway. The target gateway receives the handover request.

1505: The target gateway sends the handover request to the target basestation based on the information about the target base station in thehandover request. The target base station receives the handover request.

1506 is basically the same as 404.

1507: The target base station sends a handover response to the targetgateway. The target gateway receives the handover response.

1508: The target gateway sends a handover response to the sourcegateway. The source gateway receives the handover response.

1509: The source gateway sends a handover response to the source basestation. The source base station receives the handover response.

1510: The source base station sends a handover response to the terminaldevice. The terminal device receives the handover response.

If the handover response contains a handover instruction for a servicesuch as a first service, steps 1511 to 1514 are correspondinglyperformed.

1511 is basically the same as 407.

1512: The target base station sends a handover acknowledgement to thetarget gateway. The target gateway receives the handoveracknowledgement. The handover acknowledgement may include informationabout a tracking area identifier and an E-UTRAN cell global identifier(E-UTRAN Cell Global Identifier, ECGI).

1513: The target gateway sends the handover acknowledgement to thesource gateway. The source gateway receives the handoveracknowledgement.

1514 is basically the same as 410.

The service may be all services of the terminal device or may be someservices of the terminal device. If the service is all the services ofthe terminal device, the foregoing method may further include steps 1515and 1516.

1515: The source gateway sends UE context release information to thesource base station. The source base station receives the UE contextrelease information. The UE context release information is used tonotify the source base station that the terminal device has been handedover to the target base station and trigger the source base station torelease a resource.

1516: The source base station releases context information of theterminal device.

If ICIC needs to be performed on a service such as a second service, thehandover response contains information about an air interface resourceof the service, and step 1517 is correspondingly performed.

FIG. 16 is a schematic interactive diagram of an inter-cell interferencecoordination method according to another embodiment of the presentpatent application. An occurrence scenario of this embodiment is similarto that of the embodiment in FIG. 13. As shown in FIG. 16, thecommunication method includes the following steps:

1601 is basically the same as 1301.

1602 is basically the same as 1302.

1603: The source base station sends the ICIC request to a sourcegateway. The source gateway receives the ICIC request. Refer to step1303 for information containd in the ICIC request. A handover requestfurther includes a tracking area identifier used to assist the sourcegateway in selecting a suitable target gateway.

1604: The source gateway selects a target gateway based on the targettracking area identifier. The source gateway sends the ICIC request tothe target gateway. The target gateway receives the ICIC request.

1605: The target gateway sends the ICIC request to the target basestation based on information about the target base station in the ICICrequest. The target base station receives the ICIC request.

1606 is basically the same as 1304.

1607: The target base station sends the ICIC response to the targetgateway. The target gateway receives the ICIC response. The ICICresponse includes information about an air interface resource. Ahandover response may further contain information of the source basestation.

1608: The source gateway sends the ICIC response to the target gateway.The target gateway receives the ICIC response.

1609: The source gateway sends the ICIC response to the source basestation. The source base station receives the ICIC response.

1610: The source base station sends the ICIC response to the terminaldevice. The terminal device receives the ICIC response.

1611: The source base station transmits a service of the terminal deviceon the air interface resource on which interference coordination isperformed.

The solutions provided in the embodiments of the present invention aremainly described above from a perspective of interaction between networkelements. It may be understood that, to implement the foregoingfunctions, the network elements include corresponding hardwarestructures and/or software modules for performing the functions. Aperson skilled in the art should be easily aware that, in combinationwith the embodiments disclosed in this specification, the present patentapplication can be implemented by using hardware or a combination ofhardware and computer software. Whether a function is performed byhardware or by computer software driving hardware depends on particularapplications and design constraint conditions of the technicalsolutions. A person skilled in the art may use different methods toimplement the described functions for each particular application, butit should not be considered that the implementation goes beyond thescope of the present patent application.

The present patent application further provides apparatus embodimentsfor implementing the steps and methods in the foregoing methodembodiments. FIG. 17 is a possible schematic structural diagram of thebase station used in the foregoing embodiments.

The base station includes: a transceiver 1701; a memory 1702, configuredto store an instruction; and a processor 1703, connected to the memory1702 and the transceiver 1701, and configured to execute theinstruction. The base station may be a source base station or a targetbase station. If the base station is a source base station, theprocessor performs, when executing the instruction, the foregoing stepssuch as receiving, sending, and obtaining of the source base station byusing the transceiver 1701. The processor 1703 further performs, whenexecuting the instruction, handover decision steps. If the base stationis a target base station, the processor performs, when executing theinstruction, the foregoing steps such as receiving, sending, andobtaining of the target base station by using the transceiver 1701. Theprocessor 1703 further performs, when executing the instruction,admission control steps.

According to an embodiment, if the base station is a source basestation, the processor 1703 performs the following steps when executingthe instruction: instructing the transceiver 1701 to send a handoverrequest to a target base station, where the handover request includesinformation about a first service of a terminal device; receiving, byusing the transceiver 1701, a handover response sent by the target basestation, where if the first service is supported by the target basestation, the handover response includes information about a handoverinstruction for the first service, and the handover instruction is usedto instruct the terminal device to hand over the first service to thetarget base station; and instructing the transceiver 1701 to send thehandover response to the terminal device.

The handover request further includes information about a second serviceof the terminal device; and if the second service is not supported bythe target base station, the handover response further includesinformation about an air interface resource of the second service, theair interface resource is determined by the target base station and onwhich interference coordination is performed, and the air interfaceresource is used by the source base station and the terminal device totransmit the second service.

The handover request further includes quality of service information ofthe second service of the terminal device, and the air interfaceresource is determined by the target base station based on the qualityof service information.

The processor 1703 further performs the following step when executingthe instruction: obtaining, by using the transceiver 1701, informationabout supported service of the target base station; and the sending ahandover request to a target base station includes: if the target basestation supports the first service, sending the handover request to thetarget base station.

The obtaining information about supported service of the target basestation includes: receiving a measurement report sent by the terminaldevice, where the measurement report includes the information about theat least one supported service of the target base station.

The obtaining information about supported service of the target basestation includes: receiving the information that is sent by a controlleror the target base station and that is about the at least one supportedservice of the target base station.

The sending a handover request to a target base station includes:sending the handover request to the target base station by using thecontroller; and the receiving a handover response sent by the targetbase station includes: receiving, by using the controller, the handoverresponse sent by the target base station.

The sending a handover request to a target base station includes:sending the handover request to the target base station by using asource gateway and a target gateway; and the receiving a handoverresponse sent by the target base station includes: receiving, by usingthe source gateway and the target gateway, the handover response sent bythe target base station.

According to an embodiment, if the base station is a target basestation, the processor performs the following steps when executing theinstruction: receiving, by using the transceiver 1701, a handoverrequest sent by a source base station, where the handover requestincludes information about a first service of a terminal device;instructing the transceiver 1701 to send a handover response to thesource base station, where if the base station supports the firstservice, the handover response includes information about a handoverinstruction for the first service, and the handover instruction is usedto instruct the terminal device to hand over the first service from thesource base station to the base station.

The handover request further includes information about a second serviceof the terminal device; and if the base station does not support thesecond service, the handover response further includes information aboutan air interface resource of the second service, the air interfaceresource is determined by the processor 1703 and on which interferencecoordination is performed, and the air interface resource is used by thesource base station and the terminal device to transmit the secondservice.

The handover request further includes quality of service information ofthe second service of the terminal device, and the air interfaceresource is determined by the base station based on the quality ofservice information.

FIG. 18 is a possible schematic structural diagram of the gateway usedin the foregoing embodiments. The gateway includes: a transceiver 1801;a memory 1802, configured to store an instruction; and a processor 1803,connected to the memory 1802 and the transceiver 1801, and configured toexecute the instruction. If the gateway shown in FIG. 18 is theforegoing source gateway, the processor 1803 performs, when executingthe instruction, the foregoing receiving and sending steps of the sourcegateway by using the transceiver 1801. If the gateway shown in FIG. 18is the foregoing target gateway, the processor 1803 performs, whenexecuting the instruction, the foregoing receiving and sending steps ofthe target gateway by using the transceiver 1801. If the gateway shownin FIG. 18 is the gateway shown in FIG. 4, the processor 1803 performs,when executing the instruction, the foregoing receiving and sendingsteps of the gateway by using the transceiver 1801.

According to an embodiment, if the gateway is a source gateway, theprocessor 1803 performs the following steps when executing theinstruction: receiving, by using the transceiver 1801, a handoverrequest sent by a source base station, where the handover requestincludes information about a first service of a terminal device;instructing the transceiver 1801 to send the handover request to atarget gateway; receiving, by using the transceiver 1801, a handoverresponse sent by the target gateway, where if the first service issupported by a target base station, the handover response includesinformation about a handover instruction for the first service, and thehandover instruction is used to instruct the terminal device to handover the first service to the target base station; and sending thehandover response to the source base station by using the transceiver1801.

The handover request further includes information about a second serviceof the terminal device; and if the second service is not supported bythe target base station, the handover response further includesinformation about an air interface resource of the second service, theair interface resource is determined by the target base station and onwhich interference coordination is performed, and the air interfaceresource is used by the terminal device and the source base station totransmit the second service.

The handover request further includes quality of service information ofthe terminal device, and the air interface resource is determined basedon the quality of service information of the terminal device.

According to an embodiment, if the gateway is a target gateway, theprocessor performs the following steps when executing the instruction:receiving, by using the transceiver 1801, a handover request sent by asource gateway, where the handover request includes information about afirst service of a terminal device; instructing the transceiver 1801 tosend the handover request to a target base station; receiving, by usingthe transceiver 1801, a handover response sent by the target basestation, where if the first service is supported by the target basestation, the handover response includes information about a handoverinstruction for the first service, and the handover instruction is usedto instruct the terminal device to hand over the first service to thetarget base station; and sending the handover response to the sourcegateway by using the transceiver 1801.

The handover request further includes information about a second serviceof the terminal device; and if the second service is not supported bythe target base station, the handover response further includesinformation about an air interface resource of the second service, theair interface resource is determined by the target base station and onwhich interference coordination is performed, and the air interfaceresource is used by the terminal device and the source base station totransmit the second service.

The handover request further includes quality of service information ofthe terminal device, and the air interface resource is determined basedon the quality of service information of the terminal device.

FIG. 19 is a possible schematic structural diagram of the terminaldevice used in the foregoing embodiments. The terminal device includes:a transceiver 1901; a memory 1902, configured to store an instruction;and a processor 1903, connected to the memory 1902 and the transceiver1901, and configured to perform, when executing the instruction, theforegoing steps such as receiving and sending of the terminal device byusing the transceiver 1901.

According to an embodiment, the processor 1903 performs the followingsteps when executing the instruction: instructing the transceiver 1901to send a measurement report to a source base station; receiving, byusing the transceiver 1901, a handover response, where if a firstservice of the terminal device is supported by a target base station,the handover response includes information about a handover instructionfor the first service, and the handover instruction is used to instructthe terminal device to hand over the first service of the terminaldevice to the target base station.

If a second service of the terminal device is not supported by thetarget base station, the handover response further includes informationabout an air interface resource of the second service, the air interfaceresource is determined by the target base station and on whichinterference coordination is performed, and the air interface resourceis used by the terminal device and the source base station to transmitthe second service.

The measurement report includes information about supported service ofthe target base station.

FIG. 20 is a possible schematic structural diagram of the base stationused in the foregoing embodiments. As shown in FIG. 20, the base stationincludes a sending unit 2010 and a receiving unit 2020. The base stationmay be a source base station or a target base station. If the basestation is a source base station, the sending unit 2010 is configured toperform the sending step of the source base station in the foregoingembodiments. The receiving unit 2020 is configured to perform thereceiving step of the source base station in the foregoing embodiments.The base station may further include a processing unit, to perform thehandover decision step of the source base station in the foregoingembodiments. In an optional implementation, the sending unit may beembodied as a transmitter to implement a function of the sending unitunder control of a processor. The receiving unit may be embodied as areceiver to implement a function of the receiving unit under the controlof the processor. The processing unit may be implemented in a form ofthe processor.

If the base station is a target base station, the sending unit 2010 isconfigured to perform the sending step of the target base station in theforegoing embodiments. The receiving unit 2020 is configured to performthe receiving step of the target base station in the foregoingembodiments. The base station may further include the processing unit toperform the admission control step of the target base station in theforegoing embodiments.

FIG. 21 a possible schematic structural diagram of the gateway used inthe foregoing embodiments. As shown in FIG. 21, the gateway includes asending unit 2110 and a receiving unit 2121. The gateway may be a sourcegateway or a target gateway or the gateway in the embodiment shown inFIG. 4. If the gateway is a source gateway, the sending unit 2110 isconfigured to perform the sending step of the source gateway in theforegoing embodiments. The receiving unit 2121 is configured to performthe receiving step of the source gateway in the foregoing embodiments.Certainly, the gateway may further include a processing unit 2030, tocomplete control and processing functions. In an optionalimplementation, the sending unit may be embodied as a transmitter toimplement a function of the sending unit under control of a processor.The receiving unit may be embodied as a receiver to implement a functionof the receiving unit under the control of the processor. The processingunit may be implemented in a form of the processor.

If the gateway is a target gateway, the sending unit 2110 is configuredto perform the sending step of the target gateway in the foregoingembodiments. The receiving unit 2121 is configured to perform thereceiving step of the target gateway in the foregoing embodiments.

If the gateway is the gateway in the embodiment shown in FIG. 4, thesending unit 2110 is configured to perform the sending step of thegateway in the embodiment shown in FIG. 4 in the foregoing embodiments.The receiving unit 2121 is configured to perform the receiving step ofthe gateway in the embodiment shown in FIG. 4 in the foregoingembodiments.

FIG. 22 is a possible schematic structural diagram of the terminaldevice used in the foregoing embodiments. As shown in FIG. 22, theterminal device includes a sending unit 2210 and a receiving unit 2222.The sending unit 2210 is configured to perform the sending step of theterminal device in the foregoing embodiments. The receiving unit 2222 isconfigured to perform the receiving step of the source terminal devicein the foregoing embodiments. Certainly, the terminal device may furtherinclude a processing unit 2030, to complete control and processingfunctions. In an optional implementation, the sending unit may beembodied as a transmitter to implement a function of the sending unitunder control of a processor. The receiving unit may be embodied as areceiver to implement a function of the receiving unit under the controlof the processor. The processing unit may be implemented in a form ofthe processor.

It may be understood that the foregoing only shows simplified designs ofnetwork elements. In actual applications, any quantity of transmitters,receivers, processors, memories, and the like may be included.

In the present patent application, service types may be categorized withdifferent granularities. Based on a coarse granularity, service typesmay be categorized into Massive M2M services, MBB services, and criticalmachine-to-machine communication services. Based on a relatively finegranularity, service types may be categorized into eight types,including: broadband access in dense area (Broadband access in densearea), broadband access everywhere (Broadband access everywhere), highuser mobility (High user mobility), massive Internet of Things cases(Massive Internet of Things Cases), extreme real time communication(Extreme real time communication), lifeline communication (Lifelinecommunication), ultra-reliable communication (Ultra-reliablecommunication), broadcast like services (Broadcast like services). Basedon a finer granularity, categorization may be performed based ondifferent scenarios, for example, 3D conferencing.

A person of ordinary skill in the art may be aware that, in combinationwith the examples described in the embodiments disclosed in thisspecification, units and algorithm steps may be implemented byelectronic hardware or a combination of computer software and electronichardware. Whether the functions are performed by hardware or softwaredepends on particular applications and design constraint conditions ofthe technical solutions. A person skilled in the art may use differentmethods to implement the described functions for each particularapplication, but it should not be considered that the implementationgoes beyond the scope of the present patent application.

It may be clearly understood by a person skilled in the art that, forthe purpose of convenient and brief description, for a detailed workingprocess of the foregoing system, apparatus, and unit, reference may bemade to a corresponding process in the foregoing method embodiments, anddetails are not described herein again.

In the several embodiments provided in this application, it should beunderstood that the disclosed system, apparatus, and method may beimplemented in other manners. For example, the described apparatusembodiment is merely an example. For example, the unit division ismerely logical function division and may be other division in actualimplementation. For example, a plurality of units or components may becombined or integrated into another system, or some features may beignored or not performed. In addition, the displayed or discussed mutualcouplings or direct couplings or communication connections may beimplemented by using some interfaces. The indirect couplings orcommunication connections between the apparatuses or units may beimplemented in electronic, mechanical, or other forms.

The units described as separate parts may or may not be physicallyseparate, and parts displayed as units may or may not be physical units,may be located in one position, or may be distributed on a plurality ofnetwork units. Some or all of the units may be selected based on actualrequirements to achieve the objectives of the solutions of theembodiments.

In addition, functional units in the embodiments of the present patentapplication may be integrated into one processing unit, or each of theunits may exist alone physically, or two or more units are integratedinto one unit.

When the functions are implemented in a form of a software functionalunit and sold or used as an independent product, the functions may bestored in a computer-readable storage medium. Based on such anunderstanding, the technical solutions of the present patent applicationessentially, or the part contributing to the prior art, or some of thetechnical solutions may be implemented in a form of a software product.The computer software product is stored in a storage medium, andincludes several instructions for instructing a computer device (whichmay be a personal computer, a server, a network device, or the like) toperform all or some of the steps of the methods described in theembodiments of the present patent application. The foregoing storagemedium includes: any medium that can store program code, such as a USBflash drive, a removable hard disk, a read-only memory (ROM, Read-OnlyMemory), a random access memory (RAM, Random Access Memory), a magneticdisk, or an optical disc.

The foregoing descriptions are merely specific implementations of thepresent patent application, but are not intended to limit the protectionscope of the present patent application. Any variation or replacementreadily figured out by a person skilled in the art within the technicalscope disclosed in the present patent application shall fall within theprotection scope of the present patent application. Therefore, theprotection scope of the present patent application shall be subject tothe protection scope of the claims.

What is claimed is:
 1. A handover method, comprising: receiving, by atarget base station, a handover request from a source base station,wherein the handover request comprises information about a first serviceof a terminal device, the information about the first service of theterminal device comprises a network slice identifier (ID); and sending,by the target base station, a handover response to the source basestation, wherein the target base station supports the first service, andthe handover response comprises information about a handover instructionfor the first service, the handover instruction to instruct the terminaldevice to hand over the first service to the target base station.
 2. Thehandover method according to claim 1, wherein the method furthercomprises: sending, by the target base station, information aboutsupported service of the target base station to the source base station.3. The handover method according to claim 1, wherein the method furthercomprises: sending, by the target base station, a path switch requestmessage, wherein the path switch request message comprises the networkslice ID.
 4. The handover method according to claim 1, wherein themethod further comprises: performing, by the target base station,admission control in response to receiving the handover request.
 5. Thehandover method according to claim 4, wherein the admission control isperformed based on the network slice ID and service type supported bythe target base station.
 6. The handover method according to claim 1,wherein the method further comprises: receiving, by the target basestation, a path switch request acknowledgement from a gateway, the pathswitch request acknowledgement to notify a completion of switching ofuplink and downlink paths on a core network side of the first service ofthe terminal device.
 7. The handover method according to claim 1,wherein the handover response further comprise a cell-radio networktemporary identifier of the terminal device in the target base stationand a dedicated random-access preamble.
 8. The handover method accordingto claim 1, wherein the method further comprises: sending, by the targetbase station, UE context release information to the source base station.9. The handover method according to claim 4, wherein the admissioncontrol is performed for a handover for all network slices, wherein thehandover response comprises information about the handover for allnetwork slices, the target base station supports all network slices ofthe terminal device, and the target base station has sufficientresources.
 10. The handover method according to claim 5, wherein theadmission control is performed for rejecting handover or handover of atleast one network slice of all network slices of the terminal device,and wherein the target base station does not have sufficient resourcesto serve the terminal device, and the handover response comprisesinformation of the rejecting handover or information about the handoverof at least one network slice of all network slices of the terminaldevice.
 11. The handover method according to claim 1, wherein the firstservice is one of multiple services, and each service of the multipleservices corresponds to a network slice.
 12. A base station, comprising:a transceiver; a memory to store instructions; and a processor coupledto the memory and the transceiver, the processor to execute theinstructions and the processor configured to perform: receiving, byusing the transceiver, a handover request from a source base station,wherein the handover request comprises information about a first serviceof a terminal device, the information about the first service of theterminal device comprises a network slice identifier (ID); instructingthe transceiver to send a handover response to the source base station,wherein if the base station supports the first service, the handoverresponse comprises information about a handover instruction for thefirst service, the handover instruction to instruct the terminal deviceto hand over the first service from the source base station to the basestation.
 13. The base station according to claim 12, wherein theprocessor is further configured to perform: instructing the transceiverto send information about supported service of the base station to thesource base station.
 14. The base station according to claim 12, whereinthe processor is further configured to perform: instructing thetransceiver to send a path switch request message, wherein the pathswitch request message comprises the network slice ID.
 15. The basestation according to claim 12, wherein the processor is furtherconfigured to perform: admission control in response to receiving thehandover request.
 16. The base station according to claim 12, whereinthe admission control is performed based on the network slice ID andservice type supported by the base station.
 17. The base stationaccording to claim 12, wherein the processor is further configured toperform: instructing the transceiver to receive a path switch requestacknowledgement from a gateway, the path switch request acknowledgementto notify a completion of switching of uplink and downlink paths on acore network side of the first service of the terminal device .
 18. Thebase station according to claim 12, wherein the handover responsefurther comprises a cell-radio network temporary identifier of theterminal device in the base station, and a dedicated random-accesspreamble.
 19. The base station according to claim 12, wherein theprocessor is further configured to perform: instructing the transceiverto send UE context release information to the source base station. 20.The base station according to claim 15, wherein the admission control isperformed for a handover for all network slices and the handoverresponse comprises information about the handover for all network slicesif the base station supports all network slices of the terminal deviceand the target base station has sufficient resources.
 21. The basestation according to claim 15, wherein the admission control isperformed for rejecting handover or handover of at least one networkslice of all network slices of the terminal device and the handoverresponse comprises information of the rejecting handover or informationabout the handover of at least one network slice of all network slicesof the terminal device if the base station does not have sufficientresources to serve the terminal device.
 22. The base station accordingto claim 12, wherein the first service is one of multiple services, andeach service of the multiple services corresponds to a network slice.